0001040971-24-000031 | 10-Q | XBRL Viewer

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Consolidated Statements of Capital - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Increase (Decrease) in Partner's Capital
Net income attributable to partnership units		$ 1,574		$ 166	$ 27,493
Acquisition of subsidiary interest from noncontrolling interest				(5,674)
DRSPP proceeds	$ 23,633	97		23,753	439
Conversion of units in the Operating Partnership for common stock	0		$ 0
Reallocation of noncontrolling interest in the Operating Partnership	(34,923)	3,126		(77,400)	(8,072)
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings	5,707	7,957		15,886	22,961
Contributions to consolidated joint venture interests				1,823
Consolidation of joint venture interest		3,266		6,678	11,714
Cash distributions to noncontrolling interests	$ (1,760)	$ (851)		$ (4,567)	$ (1,614)
Common Stock
Increase (Decrease) in Partner's Capital
DRSPP proceeds (in shares)	340	3		342	15
DRSPP proceeds	$ 3			$ 3
Conversion of common units (shares)	77		77
Conversion of units in the Operating Partnership for common stock
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in units)	4	8		90	3
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings
Common Stock \| Partners' Interest
Increase (Decrease) in Partner's Capital
Net income attributable to partnership units	914
Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Acquisition of subsidiary interest from noncontrolling interest				$ (5,674)
Contributions to consolidated joint venture interests				1,823
Consolidation of joint venture interest		3,266		6,678	$ 11,714
Cash distributions to noncontrolling interests	(1,760)	(851)		(4,567)	(1,614)
SL Green Operating Partnership
Increase (Decrease) in Partner's Capital
Beginning balance	3,757,761	4,159,833	$ 4,646,922	3,855,925	4,646,922	$ 4,646,922
Net income (loss)	(11,440)	(22,023)		4,599	(417,138)
Net income attributable to partnership units	914			166
Acquisition of subsidiary interest from noncontrolling interest				(5,674)
Other comprehensive income (loss)	(67,679)	11,847		(44,785)	20,012
Perpetual preferred unit dividends	(3,738)	(3,738)		(11,213)	(11,213)
DRSPP proceeds	23,633	97		23,753	439
Conversion of units in the Operating Partnership for common stock			0	0
Reallocation of noncontrolling interest in the Operating Partnership	(34,923)	3,126		(77,400)	(8,072)
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings	5,707	7,957		15,886	22,961
Contributions to consolidated joint venture interests				1,823
Consolidation of joint venture interest		3,266		6,678	11,714
Cash distributions to noncontrolling interests	(1,760)	(851)		(4,567)	(1,614)
Cash distributions declared	(48,470)	(52,271)		(145,186)	(156,768)
Ending balance	3,620,005	4,107,243	4,159,833	3,620,005	4,107,243	3,855,925
SL Green Operating Partnership \| Series I Preferred Stock \| Series I Preferred Stock
Increase (Decrease) in Partner's Capital
Beginning balance	221,932	221,932	221,932	221,932	221,932	221,932
Ending balance	221,932	221,932	221,932	221,932	221,932	221,932
SL Green Operating Partnership \| Common Stock
Increase (Decrease) in Partner's Capital
Net income (loss)	(10,455)
Net income attributable to partnership units	914			166
SL Green Operating Partnership \| Common Stock \| Partners' Interest
Increase (Decrease) in Partner's Capital
Beginning balance	$ 3,428,993	$ 3,813,223	$ 4,313,497	$ 3,546,906	$ 4,313,497	$ 4,313,497
Beginning balance (units)	64,814	64,387	64,380	64,726	64,380	64,380
Net income (loss)		$ (20,229)		$ 8,749	$ (412,679)
Perpetual preferred unit dividends	$ (3,738)	$ (3,738)		$ (11,213)	$ (11,213)
DRSPP proceeds (in shares)	340	3		342	15
DRSPP proceeds	$ 23,633	$ 97		$ 23,753	$ 439
Conversion of common units (shares)	77			77
Reallocation of noncontrolling interest in the Operating Partnership	$ (34,923)	$ 3,126		$ (77,400)	$ (8,072)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in units)	4	8		90	3
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings	$ 5,707	$ 7,957		$ 15,886	$ 22,961
Cash distributions declared	(48,470)	(52,271)		(145,186)	(156,768)
Ending balance	$ 3,361,661	$ 3,748,165	$ 3,813,223	$ 3,361,661	$ 3,748,165	$ 3,546,906
Ending balance (units)	65,235	64,398	64,387	65,235	64,398	64,726
SL Green Operating Partnership \| Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Partner's Capital
Beginning balance	$ 40,371	$ 57,769	$ 49,604	$ 17,477	$ 49,604	$ 49,604
Other comprehensive income (loss)	(67,679)	11,847		(44,785)	20,012
Ending balance	(27,308)	69,616	57,769	(27,308)	69,616	17,477
SL Green Operating Partnership \| Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Beginning balance	66,465	66,909	61,889	69,610	61,889	61,889
Net income (loss)	(985)	(1,794)		(4,150)	(4,459)
Acquisition of subsidiary interest from noncontrolling interest				(5,674)
Contributions to consolidated joint venture interests				1,823
Consolidation of joint venture interest		3,266		6,678	11,714
Cash distributions to noncontrolling interests	(1,760)	(851)		(4,567)	(1,614)
Ending balance	$ 63,720	$ 67,530	$ 66,909	$ 63,720	$ 67,530	$ 69,610

Corporate Indebtedness - Schedule of Senior Unsecured Notes (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Debt disclosures by scheduled maturity date
Unsecured term loans, net	$ 1,246,180	$ 1,244,881
Senior unsecured notes
Debt disclosures by scheduled maturity date
Unpaid principal balance	100,000
Unsecured term loans, net	100,000	100,000
Deferred financing costs, net	(128)	(205)
Accreted balance, net of deferred financing costs	99,872	99,795
Senior unsecured notes \| 4.27% Senior unsecured notes maturing on December 17, 2025
Debt disclosures by scheduled maturity date
Unpaid principal balance	100,000
Unsecured term loans, net	$ 100,000	$ 100,000
Coupon rate (as a percent)	4.27%
Initial Term (in Years)	10 years

Deferred Costs

9 Months Ended

Sep. 30, 2024

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Deferred Costs

Deferred costs as of September 30, 2024 and December 31, 2023 consisted of the following (in thousands):


	September 30, 2024		December 31, 2023
Deferred leasing costs	$	409,205	$	399,224
Less: accumulated amortization	(303,559)		(287,761)
Deferred costs, net	$	105,646	$	111,463

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2024

Fair Value Disclosures [Abstract]

Schedule of Fair Value Measurements, Recurring and Nonrecurring

The following tables set forth the assets and liabilities that we measure at fair value on a recurring and non-recurring basis by their levels in the fair value hierarchy as of September 30, 2024 and December 31, 2023 (in thousands):


	September 30, 2024
	Total		Level 1		Level 2		Level 3
Assets:
Marketable securities available-for-sale	$	16,522	$	—	$	16,522	$	—
Interest rate cap and swap agreements (included in Other assets)	17,026		—		17,026		—
Real estate loans held by consolidated securitization vehicles	586,823		—		586,823		—
Liabilities:
Interest rate cap and swap agreements (included in Other liabilities)	$	29,372	$	—	$	29,372	$	—
Senior obligations of consolidated securitization vehicles	571,711		—		571,711		—
Secured borrowing (1)	237,454		—		—		237,454

(1)The Company admitted an additional partner to the One Madison Avenue development project with the partner's indirect ownership in the joint venture totaling 25.0%. The transaction did not meet sale accounting under ASC 860 and, as a result, was treated as a secured borrowing for accounting purposes and is included in Other liabilities in our consolidated balance sheets.


	December 31, 2023
	Total		Level 1		Level 2		Level 3
Assets:
Marketable securities available-for-sale	$	9,591	$	—	$	9,591	$	—
Interest rate cap and swap agreements (included in Other assets)	33,456		—		33,456		—

Liabilities:
Interest rate cap and swap agreements (included in Other liabilities)	$	17,108	$	—	$	17,108	$	—

Schedule of Fair Value, by Balance Sheet Grouping

The following table provides the carrying value and fair value of these financial instruments as of September 30, 2024 and December 31, 2023 (in thousands):


	September 30, 2024				December 31, 2023
	Carrying Value (1)		Fair Value		Carrying Value (1)		Fair Value

Debt and preferred equity investments	$	293,924	(2)		$	346,745	(2)

Fixed rate debt	$	3,287,898	$	3,252,374	$	3,237,386	$	3,184,338
Variable rate debt (3)	545,900		545,282		270,000		268,787
	$	3,833,798	$	3,797,656	$	3,507,386	$	3,453,125

(1)Amounts exclude net deferred financing costs.

(2)As of September 30, 2024, debt and preferred equity investments had an estimated fair value of approximately $0.3 billion. As of December 31, 2023, debt and preferred equity investments had an estimated fair value of approximately $0.3 billion.

(3)As of September 30, 2024, variable rate debt with a carrying value of $60.9 million and fair value of $60.1 million is included in the Company's alternative strategy portfolio.

Partners' Capital of the Operating Partnership - EPS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Numerator
Less: distributed earnings allocated to participating securities	$ (435)	$ (408)	$ (1,309)	$ (1,225)
Net loss attributable to SLGOP common unitholders (numerator for basic earnings per unit)	(13,714)	(24,375)	(3,607)	(425,117)
Net Income (Loss) Available to Common Stockholders, Diluted	$ (13,714)	$ (25,949)	$ (3,607)	$ (452,610)
Denominator
Common stock shares excluded from the diluted shares outstanding (shares)	5,345,430	1,402,771	5,155,662	1,380,364
SL Green Operating Partnership
Numerator
Net loss attributable to SLGOP common unitholders	$ (14,193)	$ (25,541)	$ (2,464)	$ (451,385)
Less: distributed earnings allocated to participating securities	(1,147)	(408)	(3,415)	(1,225)
Net loss attributable to SLGOP common unitholders (numerator for basic earnings per unit)	(15,340)	(25,949)	(5,879)	(452,610)
Net Income (Loss) Available to Common Stockholders, Diluted	$ (15,340)	$ (25,949)	$ (5,879)	$ (452,610)
Denominator
Basic weighted average common units outstanding (in shares)	67,999,000	68,296,000	68,092,000	68,274,000
Diluted weighted average common units outstanding (shares)	67,999,000	68,296,000	68,092,000	68,274,000
Common stock shares excluded from the diluted shares outstanding (shares)	1,734,283	1,402,771	1,418,306	1,380,364

Significant Accounting Policies - Investment in Commercial Real Estate Properties - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended			9 Months Ended
	Apr. 30, 2024	Sep. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Rental revenue decrease from amortization of acquired leases		$ 0.8		$ 0.1	$ 1.7	$ 14.3
719 Seventh Avenue
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Write down of value in leasehold interest			$ 46.3
719 Seventh Avenue \| Mathias \| Related party
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Proceeds from sale of property	$ 30.5
760 Madison Avenue
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Write down of value in leasehold interest					13.7
Interest capitalized					$ 13.2
Minimum \| Below-Market Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful life of other intangible assets (in years)		1 year			1 year
Minimum \| Above-Market Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful life of other intangible assets (in years)		1 year			1 year
Minimum \| In-Place Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful life of other intangible assets (in years)		1 year			1 year
Minimum \| Building
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful life (in years)		3 years			3 years
Maximum \| Below-Market Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful life of other intangible assets (in years)		15 years			15 years
Maximum \| Above-Market Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful life of other intangible assets (in years)		15 years			15 years
Maximum \| In-Place Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful life of other intangible assets (in years)		15 years			15 years
Maximum \| Building
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful life (in years)		40 years			40 years

- Details

Name:	srt_CounterpartyNameAxis=slg_AndrewMathiasMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Investments in Unconsolidated Joint Ventures - Schedule of Investments in Unconsolidated Joint Ventures Sold (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended			9 Months Ended
	May 31, 2024	Jan. 31, 2024	Sep. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
Loss on Sale			$ 371		$ 0	$ 19,006	$ (79)
Employee-related liabilities			7,800			7,800
Carrying Value			293,924			293,924		$ 346,745
Depreciable real estate reserves and impairment			0		$ 389	(65,839)	$ (305,527)
Preferred Equity (4)
Schedule of Equity Method Investments [Line Items]
Carrying Value			134,474			134,474
625 Madison Avenue \| Preferred Equity (4)
Schedule of Equity Method Investments [Line Items]
Carrying Value			209,900			209,900
625 Madison Avenue
Schedule of Equity Method Investments [Line Items]
Depreciable real estate reserves and impairment				$ 5,900
625 Madison Avenue \| Preferred Equity (4)
Schedule of Equity Method Investments [Line Items]
Carrying value of investment in leasehold interest			$ 235,400			$ 235,400
Average yield (as a percent)						8.91%
717 Fifth Avenue \| Joint venture \| Wharton Properties
Schedule of Equity Method Investments [Line Items]
Ownership Interest Sold		10.92%
Gross Asset Valuation		$ 963,000
Loss on Sale		$ 24,900
625 Madison Avenue \| Joint venture \| Wharton Properties
Schedule of Equity Method Investments [Line Items]
Ownership Interest Sold	90.43%
Gross Asset Valuation	$ 634,600
Loss on Sale	$ (7,600)

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (9,264)	$ (21,694)	$ 11,084	$ (439,279)
Other comprehensive (loss) income:
(Decrease) increase in unrealized value of derivative instruments, including SL Green's share of joint venture derivative instruments	(72,168)	12,799	(49,052)	23,062
(Decrease) increase in unrealized value of marketable securities	(228)	(181)	1,170	(1,625)
Other comprehensive (loss) income	(72,396)	12,618	(47,882)	21,437
Comprehensive loss	(81,660)	(9,076)	(36,798)	(417,842)
Net (income) loss attributable to noncontrolling interests and preferred units distributions	(277)	1,465	(2,169)	26,600
Other comprehensive loss (income) attributable to noncontrolling interests	4,717	(771)	3,097	(1,425)
Comprehensive loss attributable to SL Green	$ (77,220)	$ (8,382)	$ (35,870)	$ (392,667)

Properties Held for Sale and Property Dispositions

9 Months Ended

Sep. 30, 2024

Discontinued Operations and Disposal Groups [Abstract]

Properties Held for Sale and Property Dispositions

Properties Held for Sale

As of September 30, 2024, no properties were classified as held for sale.

Property Dispositions

The following table summarizes the properties sold during the nine months ended September 30, 2024:


Property	Disposition Date	Property Type	Unaudited Approximate Usable Square Feet	Sales Price (1) (in millions)		(Loss) Gain on Sale (in millions) (2)
719 Seventh Avenue	June 2024	Fee Interest	10,040	$	30.5	$	(2.0)
Palisades Premier Conference Center	July 2024	Fee Interest	450,000	26.3		$	7.3

(1)Sales price represents the gross sales price for a property or the gross asset valuation for interests in a property.

(2)The loss on sale is net of $4.1 million of employee compensation accrued in connection with the realization of the investment disposition. The amounts do not include adjustments for expenses recorded in subsequent periods.

Financial Instruments: Derivatives and Hedging (Tables)

9 Months Ended

Sep. 30, 2024

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Notional and Fair Value of Derivative Financial Instruments and Foreign Currency Hedges

The following table summarizes the notional value at inception and fair value of our consolidated derivative financial instruments as of September 30, 2024 based on Level 2 information. The notional value is an indication of the extent of our involvement in these instruments at that time, but does not represent exposure to credit, interest rate or market risks (dollars in thousands).


	Notional Value		Strike Rate		Effective Date	Expiration Date	Balance Sheet Location	Fair Value
Interest Rate Cap	$	205,000	4.000	%	February 2024	February 2025	Other Assets	$	395
Interest Rate Cap	370,000		3.250	%	June 2024	June 2025	Other Assets	2,287
Interest Rate Cap	370,000		3.250	%	June 2024	June 2025	Other Liabilities	(2,275)
Interest Rate Cap	68,678		4.000	%	August 2024	July 2025	Other Liabilities	(161)
Interest Rate Swap	150,000		2.621	%	December 2021	January 2026	Other Assets	1,870
Interest Rate Swap	200,000		2.662	%	December 2021	January 2026	Other Assets	2,393
Interest Rate Swap	125,000		3.667	%	August 2024	December 2026	Other Liabilities	(826)
Interest Rate Swap	125,000		3.670	%	August 2024	December 2026	Other Liabilities	(841)
Interest Rate Swap	100,000		2.903	%	February 2023	February 2027	Other Assets	991
Interest Rate Swap	100,000		2.733	%	February 2023	February 2027	Other Assets	1,374
Interest Rate Swap	50,000		2.463	%	February 2023	February 2027	Other Assets	992
Interest Rate Swap	200,000		2.591	%	February 2023	February 2027	Other Assets	3,391
Interest Rate Swap	300,000		2.866	%	July 2023	May 2027	Other Assets	3,333
Interest Rate Swap	150,000		3.524	%	January 2024	May 2027	Other Liabilities	(792)
Interest Rate Swap	370,000		3.888	%	November 2022	June 2027	Other Liabilities	(5,513)
Interest Rate Swap	68,678		4.466	%	August 2024	June 2027	Other Liabilities	(2,076)
Interest Rate Swap	300,000		4.487	%	November 2024	November 2027	Other Liabilities	(10,723)
Interest Rate Swap	100,000		3.756	%	January 2023	January 2028	Other Liabilities	(1,482)
Interest Rate Swap	204,963		3.915	%	February 2025	May 2028	Other Liabilities	(4,683)
								$	(12,346)

The following table summarizes the notional value at inception and fair value of our joint ventures' derivative financial instruments as of September 30, 2024 based on Level 2 information. The notional value is an indication of the extent of our involvement in these instruments at that time, but does not represent exposure to credit, interest rate or market risks (dollars in thousands).


	Notional Value		Strike Rate		Effective Date	Expiration Date	Classification	Fair Value
Interest Rate Cap	$	312,783	4.000	%	May 2024	November 2024	Asset	$	294
Interest Rate Cap	312,783		4.000	%	May 2024	November 2024	Asset	294
Interest Rate Cap	285,000		4.000	%	August 2024	July 2025	Asset	671
Interest Rate Swap	250,000		3.608	%	April 2023	February 2026	Liability	(67)
Interest Rate Swap	250,000		3.608	%	April 2023	February 2026	Liability	(67)
Interest Rate Swap	177,000		1.555	%	December 2022	February 2026	Asset	4,836
Interest Rate Swap	268,750		4.039	%	July 2024	September 2028	Liability	(7,984)
Interest Rate Swap	268,750		4.058	%	July 2024	September 2028	Liability	(8,176)
Interest Rate Swap	537,500		4.065	%	July 2024	September 2028	Liability	(16,710)
								$	(26,909)

Schedule of Effect of Derivative Financial Instruments on Consolidated Statements of Income

The following table presents the effect of our derivative financial instruments and our share of our joint ventures' derivative financial instruments that are designated and qualify as hedging instruments on the consolidated statements of operations for the three months ended September 30, 2024 and 2023, respectively (in thousands):


	Amount of Gain Recognized in Other Comprehensive (Loss) Income				Location of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income	Amount of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income
	Three Months Ended September 30,					Three Months Ended September 30,
Derivative	2024		2023			2024		2023
Interest Rate Swaps/Caps	$	(38,205)	$	24,910	Interest expense	$	10,248	$	11,422
Share of unconsolidated joint ventures' derivative instruments	(19,493)		3,927		Equity in net (loss) income from unconsolidated joint ventures	4,222		4,616
	$	(57,698)	$	28,837		$	14,470	$	16,038

The following table presents the effect of our derivative financial instruments and our share of our joint ventures' derivative financial instruments that are designated and qualify as hedging instruments on the consolidated statements of operations for the nine months ended September 30, 2024 and 2023, respectively (in thousands):


	Amount of Gain Recognized in Other Comprehensive (Loss) Income				Location of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income	Amount of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income
	Nine Months Ended September 30,					Nine Months Ended September 30,
Derivative	2024		2023			2024		2023
Interest Rate Swaps/Caps	$	4,143	$	52,624	Interest expense	$	29,746	$	31,043
Share of unconsolidated joint ventures' derivative instruments	(11,951)		13,467		Equity in net (loss) income from unconsolidated joint ventures	11,498		11,986
	$	(7,808)	$	66,091		$	41,244	$	43,029

- Definition

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

+ References + Details

Financial Instruments: Derivatives and Hedging

9 Months Ended

Sep. 30, 2024

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Financial Instruments: Derivatives and Hedging

In the normal course of business, we use a variety of commonly used derivative instruments, including, but not limited to, interest rate swaps, caps, collars and floors, to manage interest rate risk. We hedge our exposure to variability in future cash flows for forecasted transactions in addition to anticipated future interest payments on existing debt. We recognize all derivatives on the balance sheet at fair value. Derivatives that are not hedges are adjusted to fair value through earnings. If a derivative is a hedge, depending on the nature of the hedge, changes in the fair value of the derivative will either be offset against the change in fair value of the hedge asset, liability, or firm commitment through earnings, or recognized in other comprehensive income (loss) until the hedged item is recognized in earnings. Reported net income and equity may increase or decrease prospectively, depending on future levels of interest rates and other variables affecting the fair values of derivative instruments and hedged items, but will have no effect on cash flows. Currently, all of our designated derivative instruments are effective hedging instruments.


	Notional Value		Strike Rate		Effective Date	Expiration Date	Balance Sheet Location	Fair Value
Interest Rate Cap	$	205,000	4.000	%	February 2024	February 2025	Other Assets	$	395
Interest Rate Cap	370,000		3.250	%	June 2024	June 2025	Other Assets	2,287
Interest Rate Cap	370,000		3.250	%	June 2024	June 2025	Other Liabilities	(2,275)
Interest Rate Cap	68,678		4.000	%	August 2024	July 2025	Other Liabilities	(161)
Interest Rate Swap	150,000		2.621	%	December 2021	January 2026	Other Assets	1,870
Interest Rate Swap	200,000		2.662	%	December 2021	January 2026	Other Assets	2,393
Interest Rate Swap	125,000		3.667	%	August 2024	December 2026	Other Liabilities	(826)
Interest Rate Swap	125,000		3.670	%	August 2024	December 2026	Other Liabilities	(841)
Interest Rate Swap	100,000		2.903	%	February 2023	February 2027	Other Assets	991
Interest Rate Swap	100,000		2.733	%	February 2023	February 2027	Other Assets	1,374
Interest Rate Swap	50,000		2.463	%	February 2023	February 2027	Other Assets	992
Interest Rate Swap	200,000		2.591	%	February 2023	February 2027	Other Assets	3,391
Interest Rate Swap	300,000		2.866	%	July 2023	May 2027	Other Assets	3,333
Interest Rate Swap	150,000		3.524	%	January 2024	May 2027	Other Liabilities	(792)
Interest Rate Swap	370,000		3.888	%	November 2022	June 2027	Other Liabilities	(5,513)
Interest Rate Swap	68,678		4.466	%	August 2024	June 2027	Other Liabilities	(2,076)
Interest Rate Swap	300,000		4.487	%	November 2024	November 2027	Other Liabilities	(10,723)
Interest Rate Swap	100,000		3.756	%	January 2023	January 2028	Other Liabilities	(1,482)
Interest Rate Swap	204,963		3.915	%	February 2025	May 2028	Other Liabilities	(4,683)
								$	(12,346)

During the three and nine months ended September 30, 2024, we recorded a loss of $9.2 million and $2.8 million, respectively, based on the changes in the fair value of forward-starting interest rate swaps, which is included in Purchase price and other fair value adjustments in the consolidated statements of operations. During the three and nine months ended September 30, 2023, we recorded a loss of $0.0 million and $0.2 million, respectively, based on the changes in the fair value of an interest rate cap we sold, which is included in Purchase price and other fair value adjustments in the consolidated statements of operations. During the three and nine months ended September 30, 2024, we recorded a gain of $0.2 million and $0.1 million, respectively, on the changes in fair value, which is included in interest expense in the consolidated statements of operations. During the three and nine months ended September 30, 2023, we recorded a loss of $0.0 million and $0.2 million, respectively, on the changes in fair value, which is included in interest expense in the consolidated statements of operations.

Certain agreements the Company has with each of its derivative counterparties contain a provision where if the Company defaults on any of its indebtedness, then the Company could also be declared in default on its derivative obligations. As of September 30, 2024, the fair value of derivatives in a net liability position, including accrued interest but excluding any adjustment for nonperformance risk related to these agreements, was ($29.7 million). As of September 30, 2024, the Company was not required to post any collateral related to these agreements and was not in breach of any agreement provisions. If the Company had breached any of these provisions, it could have been required to settle its obligations under the agreements at their aggregate termination value of $31.0 million as of September 30, 2024.

Gains and losses on terminated hedges are included in accumulated other comprehensive income, and are recognized into earnings over the term of the related obligation. Over time, the realized and unrealized gains and losses held in accumulated other comprehensive income will be reclassified into earnings as an adjustment to interest expense in the same periods in which the hedged interest payments affect earnings. We estimate that ($11.2 million) of the current balance held in accumulated other comprehensive income will be reclassified into interest expense and $1.3 million of the portion related to our share of joint venture accumulated other comprehensive income will be reclassified into equity in net loss from unconsolidated joint ventures within the next 12 months.


	Amount of Gain Recognized in Other Comprehensive (Loss) Income				Location of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income	Amount of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income
	Three Months Ended September 30,					Three Months Ended September 30,
Derivative	2024		2023			2024		2023
Interest Rate Swaps/Caps	$	(38,205)	$	24,910	Interest expense	$	10,248	$	11,422
Share of unconsolidated joint ventures' derivative instruments	(19,493)		3,927		Equity in net (loss) income from unconsolidated joint ventures	4,222		4,616
	$	(57,698)	$	28,837		$	14,470	$	16,038

The following table presents the effect of our derivative financial instruments and our share of our joint ventures' derivative financial instruments that are designated and qualify as hedging instruments on the consolidated statements of operations for the nine months ended September 30, 2024 and 2023, respectively (in thousands):


	Amount of Gain Recognized in Other Comprehensive (Loss) Income				Location of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income	Amount of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income
	Nine Months Ended September 30,					Nine Months Ended September 30,
Derivative	2024		2023			2024		2023
Interest Rate Swaps/Caps	$	4,143	$	52,624	Interest expense	$	29,746	$	31,043
Share of unconsolidated joint ventures' derivative instruments	(11,951)		13,467		Equity in net (loss) income from unconsolidated joint ventures	11,498		11,986
	$	(7,808)	$	66,091		$	41,244	$	43,029


	Notional Value		Strike Rate		Effective Date	Expiration Date	Classification	Fair Value
Interest Rate Cap	$	312,783	4.000	%	May 2024	November 2024	Asset	$	294
Interest Rate Cap	312,783		4.000	%	May 2024	November 2024	Asset	294
Interest Rate Cap	285,000		4.000	%	August 2024	July 2025	Asset	671
Interest Rate Swap	250,000		3.608	%	April 2023	February 2026	Liability	(67)
Interest Rate Swap	250,000		3.608	%	April 2023	February 2026	Liability	(67)
Interest Rate Swap	177,000		1.555	%	December 2022	February 2026	Asset	4,836
Interest Rate Swap	268,750		4.039	%	July 2024	September 2028	Liability	(7,984)
Interest Rate Swap	268,750		4.058	%	July 2024	September 2028	Liability	(8,176)
Interest Rate Swap	537,500		4.065	%	July 2024	September 2028	Liability	(16,710)
								$	(26,909)

Share-based Compensation - Additional Information (Details)		3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 01, 2008 shares	Sep. 30, 2024 USD ($) unit / shares unit fungibleUnit shares	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) unit / shares unit fungibleUnit shares	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capitalized to assets associated with compensation expense related to our long-term compensation plans, restricted stock and stock options		$ 400,000	$ 300,000	$ 1,300,000	$ 1,000,000.0
All Other Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fungible units per share (in fungible units per share) \| unit / shares		1.0		1.0
Expected term				10 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of commencement of option vesting, from date of grant (in years)				1 year
Options granted (in shares) \| shares				0		0
Remaining weighted average contractual life of the options outstanding (in years)				2 years 2 months 12 days
Remaining average contractual life of the options exercisable (in years)				2 years 2 months 12 days
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period (in years)				5 years
Options vesting period (in years)				1 year
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period (in years)				10 years
Options vesting period (in years)				5 years
Class O LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred unit distributions as a percentage of common unit distributions		10.00%		10.00%
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense				$ 7,935,369		$ 7,766,055
Total unrecognized compensation cost related to unvested stock awards		$ 12,200,000		$ 12,200,000
Annual award vesting rate, low end of range (as a percent)				15.00%
Annual award vesting rate, high end of range (as a percent)				35.00%
Fair value of restricted stock vested during the period				$ 7,100,000		10,200,000
Weighted average period for recognition of compensation cost related to unvested stock awards (in years)				2 years
Weighted average fair value of options granted during the period				$ 394,851		$ 15,789,540
Awards granted (in shares) \| shares				7,734		337,350
Awards outstanding (in shares) \| shares		4,086,858		4,086,858		4,089,174	3,758,174
LTIP units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of options granted during the period				$ 23,600,000		$ 38,100,000
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 6,700,000	10,600,000	19,700,000	31,200,000
Total unrecognized compensation cost related to unvested stock awards		$ 28,500,000		$ 28,500,000
Weighted average period for recognition of compensation cost related to unvested stock awards (in years)				1 year 7 months 6 days
Third Amendment and Restated 2005 Stock Option and Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum fungible units that may be granted (in shares) \| unit		32,210,000		32,210,000
Fungible units per share (in fungible units per share) \| unit / shares		2.59		2.59
Shares that may be issued if equal to fungible units (shares) (less than) \| shares		32,210,000		32,210,000
Fungible units \| fungibleUnit		3,500,000		3,500,000
Third Amendment and Restated 2005 Stock Option and Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 0	0	$ 0	0
Total unrecognized compensation cost related to unvested stock awards		$ 0		$ 0
Stock Options, Stock Appreciation Rights and Other Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fungible units per share (in fungible units per share) \| unit / shares		0.84		0.84
Award expiration period (in years)				5 years
Deferred Stock Compensation Plan for Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 200,000	$ 200,000	$ 2,600,000	$ 2,500,000
Maximum percentage of the annual retainer fee, chairman fees and meeting fees that may be deferred by non-employee directors (percent)		100.00%		100.00%
Awards granted (in shares) \| shares				15,945
Shares issued (in shares) \| shares				25,590
Awards outstanding (in shares) \| shares		125,654		125,654
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance (shares) \| shares	500,000
Duration of each offering period starting the first day of each calendar quarter (in months)	3 months
Discount from market price	85.00%
Shares of common stock issued (shares) \| shares		241,790		241,790

Property Acquisitions and Consolidations (Details) $ in Thousands	1 Months Ended	9 Months Ended
	Mar. 31, 2024 USD ($) ft²	Sep. 30, 2024 USD ($) property	Dec. 31, 2023 USD ($)
Real Estate [Line Items]
Number of real estate properties acquired from third party \| property		0
Investments in unconsolidated joint ventures		$ 2,871,683	$ 2,983,313
10 East 53rd Street
Real Estate [Line Items]
Acquire its partner's interest	45.00%
Investments in unconsolidated joint ventures	$ 7,200
Investment fair value adjustment	$ 55,700
10 East 53rd Street
Real Estate [Line Items]
Unaudited Approximate Usable Square Feet \| ft²	354,300
Gross Asset Valuation (in millions)	$ 236,000

- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References + Details

Significant Accounting Policies - Investment in CMBS Securitization Trusts (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Fair Value [Abstract]
Real estate loans held by consolidated securitization vehicles	$ 586,823	$ 0
Senior obligations of consolidated securitization vehicles	571,711	0
Principal Value
Servicing asset at amortized cost	126,400
Servicing liability at amortized cost, balance	32,200
Real estate loans held by consolidated securitization vehicles
Fair Value [Abstract]
Real estate loans held by consolidated securitization vehicles	713,218	0
Principal Value
Real estate loans held by consolidated securitization vehicles	894,000	0
Accrued interest income	3,400
Senior obligations of consolidated securitization vehicles
Fair Value [Abstract]
Senior obligations of consolidated securitization vehicles	603,902	0
Principal Value
Senior obligations of consolidated securitization vehicles	703,675	0
Accrued interest expense	2,300
Securitization Vehicles, Real Estate Loans In Excess Of Senior Obligations
Fair Value [Abstract]
Real estate loans held by consolidated securitization vehicles in excess of senior obligations of consolidated securitization vehicles	109,316	0
Principal Value
Real estate loans held by consolidated securitization vehicles in excess of senior obligations of consolidated securitization vehicles	$ 190,325	$ 0

Organization and Basis of Presentation

9 Months Ended

Sep. 30, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Basis of Presentation

SL Green Realty Corp., which is referred to as the Company or SL Green, a Maryland corporation, and SL Green Operating Partnership, L.P., which is referred to as SLGOP or the Operating Partnership, a Delaware limited partnership, were formed in June 1997 for the purpose of combining the commercial real estate business of S.L. Green Properties, Inc. and its affiliated partnerships and entities. The Operating Partnership received a contribution of interest in the real estate properties, as well as 95% of the economic interest in the management, leasing and construction companies which are referred to as S.L. Green Management Corp, or the Service Corporation. All of the management, leasing and construction services that are provided to the properties that are wholly-owned by us and that are provided to certain joint ventures are conducted through SL Green Management LLC and S.L. Green Management Corp., respectively, which are 100% owned by the Operating Partnership. The Company has qualified, and expects to qualify in the current fiscal year, as a real estate investment trust, or REIT, under the Internal Revenue Code of 1986, as amended, or the Code, and operates as a self-administered, self-managed REIT. A REIT is a legal entity that holds real estate interests and, through payments of dividends to stockholders, is permitted to minimize the payment of Federal income taxes at the corporate level. Unless the context requires otherwise, all references to "we," "our" and "us" means the Company and all entities owned or controlled by the Company, including the Operating Partnership.

Substantially all of our assets are held by, and all of our operations are conducted through, the Operating Partnership. The Company is the sole managing general partner of the Operating Partnership. As of September 30, 2024, noncontrolling investors held, in the aggregate, a 6.42% limited partnership interest in the Operating Partnership. We refer to these interests as the noncontrolling interests in the Operating Partnership. The Operating Partnership is considered a variable interest entity, or VIE, in which we are the primary beneficiary. See Note 11, "Noncontrolling Interests on the Company's Consolidated Financial Statements."

On September 30, 2024, we owned the following interests in properties in the New York metropolitan area, primarily in midtown Manhattan. Our investments located outside of Manhattan are referred to as the Suburban properties:


		Consolidated			Unconsolidated		Total
Location	Property Type	Number of Buildings		Approximate Square Feet (unaudited)	Number of Buildings	Approximate Square Feet (unaudited)	Number of Buildings	Approximate Square Feet (unaudited)	Weighted Average Leased Occupancy (1) (unaudited)
Commercial:
Manhattan	Office	14		8,753,441	10	13,009,149	24	21,762,590	89.9	%
	Retail	1		22,648	1	12,946	2	35,594	100.0	%
	Development/Redevelopment	2	(2)	880,771	1	1,385,484	3	2,266,255	N/A

		17		9,656,860	12	14,407,579	29	24,064,439	89.9	%
Suburban	Office	7		862,800	—	—	7	862,800	73.6	%



Total commercial properties		24		10,519,660	12	14,407,579	36	24,927,239	89.3	%
Residential:
Manhattan	Residential	1	(2)	140,382	1	221,884	2	362,266	99.0	%

Total core portfolio		25		10,660,042	13	14,629,463	38	25,289,505	89.4	%

	Alternative Strategy Portfolio (3)	1		7,848	8	3,694,956	9	3,702,804	49.4	%

(1)The weighted average leased occupancy for commercial properties represents the total leased square footage divided by the total square footage at acquisition. The weighted average leased occupancy for residential properties represents the total leased units divided by the total available units. Properties under construction are not included in the calculation of weighted average leased occupancy.

(2)As of September 30, 2024, we owned a building at 7 Dey Street / 185 Broadway that was comprised of approximately 140,382 square feet (unaudited) of residential space and approximately 50,206 square feet (unaudited) of office and retail space that is under development. For the purpose of this report, we have included this building in the number of residential properties we own. However, we have included only the residential square footage in the residential approximate square footage, and have listed the balance of the square footage as development square footage.

(3)Represents non-core assets.

As of September 30, 2024, we also managed one office building and one retail building owned by third parties encompassing approximately 0.4 million square feet (unaudited), and held debt and preferred equity investments with a book value of $293.9 million, excluding debt and preferred equity investments and other financing receivables totaling $9.3 million that are included in balance sheet line items other than the Debt and preferred equity investments line item.

Partnership Agreement

In accordance with the partnership agreement of the Operating Partnership, or the Operating Partnership Agreement, we allocate all distributions and profits and losses in proportion to the percentage of ownership interests of the respective partners, subject to the priority distributions with respect to preferred units and special provisions that apply to Long Term Incentive Plan ("LTIP") Units. As the managing general partner of the Operating Partnership, we are required to take such reasonable efforts, as determined by us in our sole discretion, to cause the Operating Partnership to distribute sufficient amounts to enable the payment of sufficient dividends by us to minimize any Federal income or excise tax at the Company level. Under the Operating Partnership Agreement, each limited partner has the right to redeem units of limited partnership interests for cash, or if we so elect, shares of SL Green's common stock on a one-for-one basis.

Basis of Quarterly Presentation

The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and notes required by accounting principles generally accepted in the United States for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for the fair presentation of the financial position of the Company and the Operating Partnership at September 30, 2024 and the results of operations for the periods presented have been included. The operating results for the period presented are not necessarily indicative of the results that may be expected for the year ending December 31, 2024. These financial statements should be read in conjunction with the financial statements and accompanying notes included in the Annual Report on Form 10-K for the year ended December 31, 2023 of the Company and the Operating Partnership.

The consolidated balance sheet at December 31, 2023 has been derived from the audited financial statements as of that date but does not include all the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements.

Property Acquisitions and Consolidations (Tables)

9 Months Ended

Sep. 30, 2024

Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]

Schedule of Business Acquisitions, by Acquisition

The following table summarizes the properties consolidated during the nine months ended September 30, 2024:

Property

Consolidation Date

Property Type

Approximate Square Feet

Gross Asset Valuation
(in millions)

10 East 53rd Street (1)

March 2024

Fee Interest

354,300

236.0

(1)In March 2024, the Company entered into an agreement to acquire its partner's 45.0% interest in the joint venture for cash consideration of $7.2 million, which is net of all outstanding debt obligations at contract signing. As a result of the contract terms, it was concluded that the joint venture is a VIE in which the Company is the primary beneficiary, and the investment was consolidated in our financial statements. Upon consolidating the entity, the assets and liabilities of the entity were recorded at fair value which resulted in the recognition of a fair value adjustment of ($55.7 million), which is included in Purchase price and other fair value adjustments in the consolidated statements of operations. Prior to March 2024, the investment was accounted for under the equity method. See Note 16, "Fair Value Measurements."

Significant Accounting Policies - Revenue Recognition - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Deferred Revenue Arrangement By Type Table [Line Items]
Days past due for income recognition on debt and preferred equity investments to be suspended	90 days
Deferred revenue	$ 154,700	$ 134,053
Unused and Unexpired Tickets
Deferred Revenue Arrangement By Type Table [Line Items]
Deferred revenue	$ 3,800	$ 2,600

Consolidated Statements of Comprehensive Income (Loss) (Partnership) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Net (loss) income	$ (9,264)	$ (21,694)	$ 11,084	$ (439,279)
Other comprehensive (loss) income:
(Decrease) increase in unrealized value of derivative instruments, including SL Green's share of joint venture derivative instruments	(72,168)	12,799	(49,052)	23,062
(Decrease) increase in unrealized value of marketable securities	(228)	(181)	1,170	(1,625)
Other comprehensive (loss) income	(72,396)	12,618	(47,882)	21,437
Comprehensive loss	(81,660)	(9,076)	(36,798)	(417,842)
Net loss attributable to noncontrolling interests	277	(1,465)	2,169	(26,600)
Other comprehensive loss (income) attributable to noncontrolling interests	4,717	(771)	3,097	(1,425)
Comprehensive loss attributable to SL Green	(77,220)	(8,382)	(35,870)	(392,667)
SL Green Operating Partnership
Net (loss) income	(9,264)	(21,694)	11,084	(439,279)
Other comprehensive (loss) income:
(Decrease) increase in unrealized value of derivative instruments, including SL Green's share of joint venture derivative instruments	(72,168)	12,799	(49,052)	23,062
(Decrease) increase in unrealized value of marketable securities	(228)	(181)	1,170	(1,625)
Other comprehensive (loss) income	(72,396)	12,618	(47,882)	21,437
Comprehensive loss	(81,660)	(9,076)	(36,798)	(417,842)
Other comprehensive loss (income) attributable to noncontrolling interests	4,717	(771)	3,097	(1,425)
Comprehensive loss attributable to SL Green	$ (75,958)	$ (8,053)	$ (29,551)	$ (414,808)

Accumulated Other Comprehensive Income (Tables)

9 Months Ended

Sep. 30, 2024

Equity [Abstract]

Schedule of Accumulated Other Comprehensive Loss

The following tables set forth the changes in accumulated other comprehensive income by component as of September 30, 2024 (in thousands):


	Net unrealized gain (loss) on derivative instruments (1)		SL Green’s share of joint venture net unrealized loss on derivative instruments (2)		Net unrealized (loss) gain on marketable securities		Total
Balance at December 31, 2023	$	25,352	$	(6,084)	$	(1,791)	$	17,477
Other comprehensive (loss) income before reclassifications	3,864		(11,035)		1,103		(6,068)
Amounts reclassified from accumulated other comprehensive (loss) income	(27,921)		(10,796)		—		(38,717)
Balance at September 30, 2024	$	1,295	$	(27,915)	$	(688)	$	(27,308)

(1)Amount reclassified from accumulated other comprehensive (loss) income is included in interest expense in the respective consolidated statements of operations. As of September 30, 2024 and December 31, 2023, the deferred net gains from these terminated hedges, which is included in accumulated other comprehensive (loss) income relating to net unrealized gain (loss) on derivative instruments, was ($0.3 million) and ($0.4 million), respectively.

(2)Amount reclassified from accumulated other comprehensive (loss) income is included in equity in net (loss) income from unconsolidated joint ventures in the respective consolidated statements of operations.

Partners' Capital of the Operating Partnership

9 Months Ended

Sep. 30, 2024

Equity [Abstract]

Partners' Capital of the Operating Partnership

Stockholders’ Equity of the Company

Common Stock

Our authorized capital stock consists of 260,000,000 shares, $0.01 par value per share, consisting of 160,000,000 shares of common stock, $0.01 par value per share, 75,000,000 shares of excess stock, at $0.01 par value per share, and 25,000,000 shares of preferred stock, par value $0.01 per share. As of September 30, 2024, 65,235,013 shares of common stock and no shares of excess stock were issued and outstanding.

Share Repurchase Program

Our Board of Directors has approved a $3.5 billion share repurchase program under which we can buy shares of our common stock.

As of September 30, 2024, 36,107,719 shares have been repurchased under the program, excluding the redemption of OP units. We did not repurchase any shares under the program during the nine months ended September 30, 2024.

Perpetual Preferred Stock

We have 9,200,000 shares of our 6.50% Series I Cumulative Redeemable Preferred Stock, or the Series I Preferred Stock, outstanding with a mandatory liquidation preference of $25.00 per share. The Series I Preferred stockholders receive annual dividends of $1.625 per share paid on a quarterly basis and dividends are cumulative, subject to certain provisions. We are entitled to redeem the Series I Preferred Stock at any time, in whole or from time to time in part, at par for cash. In August 2012, we received $221.9 million in net proceeds from the issuance of the Series I Preferred Stock, which were recorded net of underwriters' discount and issuance costs, and contributed the net proceeds to the Operating Partnership in exchange for 9,200,000 units of 6.50% Series I Cumulative Redeemable Preferred Units of limited partnership interest, or the Series I Preferred Units.

Dividend Reinvestment and Stock Purchase Plan ("DRSPP")

In February 2024, the Company filed a new registration statement with the SEC for our dividend reinvestment and stock purchase plan, or DRSPP, which automatically became effective upon filing. The Company registered 3,500,000 shares of our common stock under the DRSPP. The DRSPP commenced on September 24, 2001.

The following table summarizes SL Green common stock issued, and proceeds received from dividend reinvestments and/or stock purchases under the DRSPP for the three and nine months ended September 30, 2024 and 2023, respectively (dollars in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Shares of common stock issued	338,704		2,695		341,180		14,736
Dividend reinvestments/stock purchases under the DRSPP	$	23,633	$	97	$	23,754	$	439

Earnings per Share

We use the two-class method of computing earnings per share (“EPS”), which is an earnings allocation formula that determines EPS for common stock and any participating securities according to dividends declared (whether paid or unpaid). Under the two-class method, basic EPS is computed by dividing the income available to common stockholders by the weighted-average number of common stock shares outstanding for the period. Diluted EPS reflects the potential dilution that could occur from share equivalent activity.

SL Green's earnings per share for the three and nine months ended September 30, 2024 and 2023 are computed as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Numerator	2024		2023		2024		2023
Basic Earnings:
Loss attributable to SL Green common stockholders	$	(13,279)	$	(23,967)	$	(2,298)	$	(423,892)
Less: distributed earnings allocated to participating securities	(435)		(408)		(1,309)		(1,225)

Net loss attributable to SL Green common stockholders (numerator for basic earnings per share)	$	(13,714)	$	(24,375)	$	(3,607)	$	(425,117)
Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares	—		—		—		—

Add back: effect of dilutive securities (redemption of units to common shares)	—		(1,574)		—		(27,493)
Net loss attributable to SL Green common stockholders (numerator for diluted earnings per share)	$	(13,714)	$	(25,949)	$	(3,607)	$	(452,610)


	Three Months Ended September 30,		Nine Months Ended September 30,
Denominator	2024	2023	2024	2023
Basic Shares:
Weighted average common stock outstanding	64,388	64,114	64,355	64,099
Effect of Dilutive Securities:
Operating Partnership units redeemable for common shares	—	4,182	—	4,175


Diluted weighted average common stock outstanding	64,388	68,296	64,355	68,274

The Company has excluded 5,345,430 and 5,155,662 common stock equivalents from the calculation of diluted shares outstanding for the three and nine months ended September 30, 2024, respectively, as they were anti-dilutive. The Company has excluded 1,402,771 and 1,380,364 common stock equivalents from the calculation of diluted shares outstanding for the three and nine months ended September 30, 2023, respectively, as they were anti-dilutive.

Partners' Capital of the Operating Partnership

The Company is the sole managing general partner of the Operating Partnership and at September 30, 2024 owned 65,235,013 general and limited partnership interests in the Operating Partnership and 9,200,000 Series I Preferred Units. Partnership interests in the Operating Partnership are denominated as “common units of limited partnership interest” (also referred to as “OP Units”) or “preferred units of limited partnership interest” (also referred to as “Preferred Units”). All references to OP Units and Preferred Units outstanding exclude such units held by the Company. A holder of an OP Unit may present such OP Unit to the Operating Partnership for redemption at any time (subject to restrictions agreed upon at the issuance of OP Units to particular holders that may restrict such right for a period of time, generally one year from issuance). Upon presentation of an OP Unit for redemption, the Operating Partnership must redeem such OP Unit in exchange for the cash equal to the then value of a share of common stock of the Company, except that the Company may, at its election, in lieu of cash redemption, acquire such OP Unit for one share of common stock. Because the number of shares of common stock outstanding at all times equals the number of OP Units that the Company owns, one share of common stock is generally the economic equivalent of one OP Unit, and the quarterly distribution that may be paid to the holder of an OP Unit equals the quarterly dividend that may be paid to the holder of a share of common stock. Each series of Preferred Units makes a distribution that is set in accordance with an amendment to the partnership agreement of the Operating Partnership. Preferred Units may also be convertible into OP Units at the election of the holder thereof or the Company, subject to the terms of such Preferred Units.

Net income (loss) allocated to the preferred unitholders and common unitholders reflects their pro rata share of net income (loss) and distributions.

Limited Partner Units

As of September 30, 2024, limited partners, other than SL Green, owned 6.42%, or 4,474,406 common units, of the Operating Partnership.

Preferred Units

Preferred units not owned by SL Green are further described in Note 11, “Noncontrolling Interests on the Company’s Consolidated Financial Statements - Preferred Units of Limited Partnership Interest in the Operating Partnership.”

Earnings per Unit

The Operating Partnership's earnings per unit for the three and nine months ended September 30, 2024 and 2023, respectively, are computed as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Numerator	2024		2023		2024		2023
Basic Earnings:
Net loss attributable to SLGOP common unitholders	$	(14,193)	$	(25,541)	$	(2,464)	$	(451,385)
Less: distributed earnings allocated to participating securities	(1,147)		(408)		(3,415)		(1,225)

Net loss attributable to SLGOP common unitholders (numerator for basic earnings per unit)	$	(15,340)	$	(25,949)	$	(5,879)	$	(452,610)


Net loss attributable to SLGOP common unitholders (numerator for diluted earnings per unit)	$	(15,340)	$	(25,949)	$	(5,879)	$	(452,610)


	Three Months Ended September 30,		Nine Months Ended September 30,
Denominator	2024	2023	2024	2023
Basic units:
Weighted average common units outstanding	67,999	68,296	68,092	68,274



Diluted weighted average common units outstanding	67,999	68,296	68,092	68,274

The Operating Partnership has excluded 1,734,283 and 1,418,306 common unit equivalents from the diluted units outstanding for the three and nine months ended September 30, 2024, respectively, as they were anti-dilutive. The Operating Partnership has excluded 1,402,771 and 1,380,364 common unit equivalents from the diluted units outstanding for the three and nine months ended September 30, 2023, respectively, as they were anti-dilutive.

Accumulated Other Comprehensive Income

The following tables set forth the changes in accumulated other comprehensive income by component as of September 30, 2024 (in thousands):


	Net unrealized gain (loss) on derivative instruments (1)		SL Green’s share of joint venture net unrealized loss on derivative instruments (2)		Net unrealized (loss) gain on marketable securities		Total
Balance at December 31, 2023	$	25,352	$	(6,084)	$	(1,791)	$	17,477
Other comprehensive (loss) income before reclassifications	3,864		(11,035)		1,103		(6,068)
Amounts reclassified from accumulated other comprehensive (loss) income	(27,921)		(10,796)		—		(38,717)
Balance at September 30, 2024	$	1,295	$	(27,915)	$	(688)	$	(27,308)

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 2
-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478448/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
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-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Publisher FASB
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

Related Party Transactions

9 Months Ended

Sep. 30, 2024

Related Party Transactions

One Vanderbilt Avenue Investment

In December 2016, we entered into agreements with entities owned and controlled by our Chairman, Chief Executive Officer ("CEO") and Interim President, Marc Holliday, and our former President, Andrew Mathias, pursuant to which they agreed to make an investment in our One Vanderbilt project (inclusive of the property and SUMMIT One Vanderbilt) at the appraised fair market value for the interests acquired. This investment entitles these entities to receive a percentage of any profits realized by the Company from its One Vanderbilt project in excess of the Company's capital contributions, of approximately 1.27% and 0.85%, respectively, on account of the property and 1.92% and 1.28%, respectively, on account of SUMMIT One Vanderbilt. The entities had no right to any return of capital. Accordingly, subject to previously disclosed repurchase rights, these interests had no value and these entities were not entitled to any amounts (other than limited distributions to cover tax liabilities incurred) unless and until the Company received distributions from the One Vanderbilt project in excess of the Company's aggregate investment in the project. The entities owned and controlled by Messrs. Holliday and Mathias paid $1.4 million and $1.0 million, respectively, which equaled the fair market value of the interests acquired as of the date the investment agreements were entered into as determined by an independent third party appraisal that we obtained.

Messrs. Holliday and Mathias have the right to tender their interests in the project upon stabilization (50% within three years after stabilization and 100% three years or more after stabilization). In addition, the agreement calls for us to repurchase these interests in the event of a sale of One Vanderbilt or a transactional change of control of the Company. We also have the right to repurchase these interests on the seven-year anniversary of the stabilization of the project or upon the occurrence of certain separation events prior to the stabilization of the project relating to each of Messrs. Holliday’s and Mathias’s continued service with us. The price paid upon a tender of the interests will equal the liquidation value of the interests at the time, with the value being based on the project's sale price, if applicable, or fair market value as determined by an independent third party appraiser. In 2022, stabilization of the property (excluding SUMMIT One Vanderbilt) was achieved. Therefore, Messrs. Holiday and Mathias exercised their rights to tender 50% of their interests in the property (excluding SUMMIT One Vanderbilt) in July 2022. In 2023, stabilization of SUMMIT One Vanderbilt was achieved.

One Vanderbilt Avenue Leases

In November 2018, we entered into a lease agreement with the One Vanderbilt Avenue joint venture covering certain floors at the property. In March 2021, the lease commenced and we relocated our corporate headquarters to the leased space. For the three and nine months ended September 30, 2024, we recorded $0.7 million and $2.2 million, respectively, of rent expense under the lease. For the three and nine months ended September 30, 2023, we recorded $0.7 million and $2.2 million, respectively, of rent expense under the lease.

Additionally, in June 2021, we, through a consolidated subsidiary, entered into a lease agreement with the One Vanderbilt Avenue joint venture for SUMMIT One Vanderbilt, which commenced operations in October 2021. For the three and nine months ended September 30, 2024, we recorded $20.8 million and $33.4 million, respectively, of rent expense under the lease, including percentage rent, of which $14.4 million and $22.7 million, respectively, was recognized as income as a component of Equity in net income (loss) from unconsolidated joint ventures in our consolidated statements of operations. For the three and nine months ended September 30, 2023, we recorded $17.0 million and $31.1 million, respectively, of rent expense under the lease, including percentage rent, of which $11.7 million and $21.0 million, respectively, was recognized as income as a component of Equity in net income (loss) from unconsolidated joint ventures in our consolidated statements of operations.

719 Seventh Avenue

In April 2024, the Company entered into an arrangement to sell the property at 719 Seventh Avenue for $30.5 million to a special purpose entity ("SPE"), of which our former President and current director, Andrew Mathias, is a partner. No amounts from the transaction will be payable to Mr. Mathias. Mr. Mathias is initially expected to own up to 40% of the equity of the SPE representing an investment by Mr. Mathias of up to approximately $7.0 million in the acquisition of the property. The transaction closed during the second quarter of 2024. See Note 4, "Properties Held for Sale and Property Dispositions."

760 Madison Avenue Condominium Unit

In July 2024, the Company entered into an agreement to sell one of the condominium units located at 760 Madison Avenue to an entity owned by a trust of which the beneficiaries are the family members of our Chairman, CEO and Interim President, Marc Holliday, for $8.4 million. The transaction is expected to close in the fourth quarter of 2024.

Other

We receive fees for providing management, leasing, construction supervision and asset management services to certain of our joint ventures as further described in Note 6, "Investments in Unconsolidated Joint Ventures." Amounts due from joint ventures, inclusive of our ownership share of the joint ventures, and related parties as of September 30, 2024 and December 31, 2023 consisted of the following (in thousands):


	September 30, 2024		December 31, 2023
Due from joint ventures	$	7,276	$	10,603
Other	5,801		1,565
Related party receivables	$	13,077	$	12,168

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-6

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(e))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

+ Details

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Operating Activities
Net income (loss)	$ (9,264)	$ (21,694)	$ 11,084	$ (439,279)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization			158,892	205,086
Equity in net (income) loss from unconsolidated joint ventures	15,428	15,126	(100,057)	44,470
Distributions of cumulative earnings from unconsolidated joint ventures			306	514
Equity in net (gain) loss on sale of interest in unconsolidated joint venture interest/real estate	(371)	0	(19,006)	79
Purchase price and other fair value adjustments			36,321	6,987
Depreciable real estate reserves and impairment			65,839	305,527
(Gain) loss on sale of real estate, net	(7,471)	(516)	(4,730)	27,813
Loan loss reserves and other investment reserves, net of recoveries	0	0	0	6,890	$ 6,890
Gain on early extinguishment of debt	0	0	(17,777)	0
Deferred rents receivable			(2,166)	(16,195)
Non-cash lease expense			15,147	15,477
Other non-cash adjustments			31,460	6,645
Changes in operating assets and liabilities:
Tenant and other receivables			(12,693)	(2,852)
Related party receivables			181	16,466
Deferred lease costs			(11,920)	(8,066)
Other assets			(11,332)	(14,169)
Accounts payable, accrued expenses, other liabilities and security deposits			(57,291)	23,655
Deferred revenue			1,616	9,978
Lease liability - operating leases			(12,454)	(7,688)
Net cash provided by operating activities			71,420	181,338
Investing Activities
Additions to land, buildings and improvements			(162,691)	(194,035)
Acquisition deposits and deferred purchase price			(12,817)	0
Investments in unconsolidated joint ventures			(371,948)	(119,522)
Distributions in excess of cumulative earnings from unconsolidated joint ventures			99,307	108,884
Net proceeds from disposition of real estate/joint venture interest			478,151	547,605
Investments in marketable securities			(5,604)	0
Investments in real estate loans held by consolidated securitization vehicles			(108,893)
Other investments			(7,350)	(17,545)
Origination of debt and preferred equity investments			(9,126)	(53,703)
Repayments or redemption of debt and preferred equity investments			63,496	0
Net cash (used in) provided by investing activities			(37,475)	271,684
Financing Activities
Proceeds from mortgages and other loans payable			900	0
Repayments of mortgages and other loans payable			(36,488)	(4,340)
Proceeds from revolving credit facility, term loans and unsecured notes			920,000	358,000
Repayments of revolving credit facility, term loans and unsecured notes			(745,000)	(808,000)
Proceeds from stock options exercised and DRSPP issuance			14,291	439
Redemption of preferred stock			0	(11,700)
Redemption of OP units			(31,491)	(8,900)
Distributions to noncontrolling interests in other partnerships			(4,567)	(1,614)
Contributions from noncontrolling interests in other partnerships			1,823	3,580
Distributions to noncontrolling interests in the Operating Partnership			(10,545)	(11,225)
Dividends paid on common and preferred stock			(162,787)	(172,920)
Other obligations related to secured borrowing			0	129,656
Deferred loan costs			(475)	(729)
Net cash used in financing activities			(54,339)	(527,753)
Net decrease in cash, cash equivalents, and restricted cash			(20,394)	(74,731)
Cash, cash equivalents, and restricted cash at beginning of year			335,519	384,054	384,054
Cash, cash equivalents, and restricted cash at end of period	315,125	309,323	315,125	309,323	335,519
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Exchange of debt investment for real estate or equity in joint venture			0	349,946
Fair value adjustment to noncontrolling interest in the Operating Partnership			77,400	8,072
Investment in joint venture			10,639	0
Deconsolidation of a subsidiary			0	101,351
Consolidation of a subsidiary			6,678	0
Consolidation of mortgage loan payable			205,000	0
Acquisition of subsidiary interest from noncontrolling interest			5,674	0
Contribution to consolidated joint venture interest			0	8,134
Extinguishment of debt			18,000	0
Debt and preferred equity investments			1,133	0
Removal of fully depreciated commercial real estate properties			4,774	7,747
Share repurchase or redemption payable			9,514	0
Consolidation of securitization vehicle assets			600,521	0
Consolidation of securitization vehicle liabilities			600,521	0
Cash and cash equivalents	188,216	189,750	188,216	189,750	221,823
Restricted cash	126,909	119,573	126,909	119,573	113,696
Total cash, cash equivalents, and restricted cash	$ 315,125	$ 309,323	$ 315,125	$ 309,323	$ 335,519

Investments in Unconsolidated Joint Ventures - Schedules of Combined Financial Statements for the Unconsolidated Joint Ventures (Details) - USD ($)
$ in Thousands

3 Months Ended

9 Months Ended

Sep. 30, 2024

Sep. 30, 2023

Sep. 30, 2024

Sep. 30, 2023

Jun. 30, 2024

Dec. 31, 2023

Jun. 30, 2023

Dec. 31, 2022

Assets

Commercial real estate property, net

$ 4,205,139

$ 4,134,860

Cash and cash equivalents

188,216

$ 189,750

188,216

$ 189,750

221,823

Tenant and other receivables

53,628

33,270

Right-of-use assets

870,782

885,929

Other assets

490,722

413,670

Total assets

^[1]

10,216,072

9,531,181

Liabilities and equity

Mortgages and other loans payable, net

1,643,992

1,491,319

Lease liability - operating leases

815,238

827,692

Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

409,844

471,401

Equity

3,620,005

4,107,243

3,620,005

4,107,243

$ 3,757,761

3,855,925

$ 4,159,833

$ 4,646,922

Total liabilities and equity

10,216,072

9,531,181

Company's investments in unconsolidated joint ventures

2,871,683

2,983,313

Investments difference between carrying amount and underlying equity

544,100

Combined statements of income for the unconsolidated joint ventures

Total revenues

229,691

210,186

640,393

701,986

Operating expenses

49,507

49,585

139,448

148,606

Real estate taxes

30,831

31,195

94,495

112,463

Operating lease rent

6,363

7,253

19,136

20,209

Interest expense, net of interest income

42,091

27,440

109,067

109,714

Amortization of deferred financing costs

1,669

2,152

4,885

6,327

Depreciation and amortization

53,176

50,642

154,007

198,760

Total expenses

244,275

227,842

668,719

756,389

Gain on early extinguishment of debt

17,777

Net (loss) income before gain (loss) on sale

(9,264)

(21,694)

11,084

(439,279)

Company's equity in net (loss) income from unconsolidated joint ventures

(15,428)

(15,126)

100,057

(44,470)

Joint venture

Assets

Commercial real estate property, net

16,534,399

17,561,406

Cash and cash equivalents

696,010

656,038

Tenant and other receivables

643,310

673,532

Debt and preferred equity investments, net

231,080

Right-of-use assets

925,461

905,934

Other assets

2,452,064

2,584,765

Total assets

21,482,324

22,381,675

Liabilities and equity

Mortgages and other loans payable, net

13,653,311

14,799,277

Deferred revenue

1,011,333

1,108,180

Lease liability - operating leases

1,011,261

990,276

Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

499,409

447,705

Equity

5,307,010

5,036,237

Total liabilities and equity

21,482,324

$ 22,381,675

Company's investments in unconsolidated joint ventures

2,871,683

Combined statements of income for the unconsolidated joint ventures

Total revenues

376,949

407,148

1,107,295

1,140,889

Operating expenses

67,104

63,081

192,587

183,825

Real estate taxes

73,686

78,564

222,797

210,428

Operating lease rent

8,487

7,307

25,990

21,746

Interest expense, net of interest income

141,067

162,897

433,117

421,528

Amortization of deferred financing costs

4,487

6,897

14,718

21,140

Depreciation and amortization

137,640

138,199

407,429

380,867

Total expenses

432,471

456,945

1,296,638

1,239,534

Gain on early extinguishment of debt

233,704

Net (loss) income before gain (loss) on sale

(55,522)

(49,797)

44,361

(98,645)

Company's equity in net (loss) income from unconsolidated joint ventures

$ (15,428)

$ (15,126)

$ 100,057

$ (44,470)

[1]

(1) The Company's consolidated balance sheets include assets and liabilities of consolidated variable interest entities ("VIEs"). See Note 2. The consolidated balance sheets include the following amounts related to our consolidated VIEs, excluding the Operating Partnership: $104.1 million and $41.2 million of land, $65.4 million and $40.5 million of building and improvements, $— million and $— million of building and leasehold improvements, $— million and $— million of right of use assets, $3.2 million and $5.4 million of accumulated depreciation, $713.2 million and $— million of real estate loans held by consolidated securitization vehicles, $776.3 million and $676.9 million of other assets included in other line items, $204.3 million and $50.0 million of real estate debt, net, $0.9 million and $0.9 million of accrued interest payable, $— million and $— million of lease liabilities, $603.9 million and $— million of senior obligations of consolidated securitization vehicles and $308.0 million and $306.5 million of other liabilities included in other line items as of September 30, 2024 and December 31, 2023, respectively.

Investments in Unconsolidated Joint Ventures (Tables)

9 Months Ended

Sep. 30, 2024

Equity Method Investments and Joint Ventures [Abstract]

Schedule of General Information on Joint Ventures and Investments in Unconsolidated Joint Ventures Sold

The table below provides general information on each of our joint ventures as of September 30, 2024:


Property	Partner	Ownership Interest (1)	Economic Interest (1)	Unaudited Approximate Square Feet
100 Park Avenue	Prudential Real Estate Investors	49.90%	49.90%	834,000
800 Third Avenue	Private Investors	60.52%	60.52%	526,000
919 Third Avenue	New York State Teacher's Retirement System	51.00%	51.00%	1,454,000
11 West 34th Street (2)	Private Investor / Wharton Properties	30.00%	30.00%	17,150
280 Park Avenue	Vornado Realty Trust	50.00%	50.00%	1,219,158
1552-1560 Broadway (2) (3)	Wharton Properties	50.00%	50.00%	57,718
650 Fifth Avenue (2) (4)	Wharton Properties	50.00%	50.00%	69,214
11 Madison Avenue	PGIM Real Estate	60.00%	60.00%	2,314,000
One Vanderbilt Avenue	National Pension Service of Korea / Hines Interest LP	71.01%	71.01%	1,657,198
Worldwide Plaza (2)	RXR Realty / New York REIT	24.95%	24.95%	2,048,725
1515 Broadway	Allianz Real Estate of America	56.87%	56.87%	1,750,000
2 Herald Square (2) (5)	Israeli Institutional Investor	95.00%	95.00%	369,000
115 Spring Street (2)	Private Investor	51.00%	51.00%	5,218
15 Beekman (6)	A fund managed by Meritz Alternative Investment Management	20.00%	20.00%	221,884
85 Fifth Avenue	Wells Fargo	36.27%	36.27%	12,946
One Madison Avenue (7)	National Pension Service of Korea / Hines Interest LP / International Investor	25.50%	25.50%	1,048,700
220 East 42nd Street	A fund managed by Meritz Alternative Investment Management	51.00%	51.00%	1,135,000
450 Park Avenue (8)	Korean Institutional Investor / Israeli Institutional Investor	50.10%	25.10%	337,000
5 Times Square (2)	RXR Realty led investment group	31.55%	31.55%	1,131,735
245 Park Avenue	U.S. Affiliate of Mori Trust Co., Ltd	50.10%	50.10%	1,782,793
625 Madison Avenue (9)	Private Investor	90.93%	90.93%	591,123

(1)Ownership interest and economic interest represent the Company's interests in the joint venture as of September 30, 2024. Changes in ownership or economic interests within the current year are disclosed in the notes below.

(2)Included in the Company's alternative strategy portfolio.

(3)The joint venture owns a long-term leasehold interest in the retail space and certain other spaces at 1560 Broadway, which is adjacent to 1552 Broadway.

(4)The joint venture owns a long-term leasehold interest in the retail space at 650 Fifth Avenue.

(5)In January 2024, the Company closed on the acquisition of interests in the joint venture that owns the leasehold interest for no consideration, which increases the Company's interest in the joint venture to 95.0%.

(6)In 2020, the Company formed a joint venture, which then entered into a long-term sublease with the Company.

(7)In 2021, the Company admitted an additional partner to the development project with the partner's indirect ownership in the joint venture totaling 25.0%. The transaction did not meet sale accounting under ASC 860 and, as a result, was treated as a secured borrowing for accounting purposes and is included in Other liabilities in our consolidated balance sheets at September 30, 2024 and December 31, 2023.

(8)The 50.1% ownership interest reflected in this table is comprised of our 25.1% economic interest and a 25.0% economic interest held by a third-party. The third-party's economic interest is held within a joint venture that we consolidate and recognize in Noncontrolling interests in other partnerships on our consolidated balance sheet. An additional third-party owns the remaining 49.9% economic interest in the property.

(9)In connection with the sale of the fee ownership interest, the Company, together with its joint venture partner, originated a $235.4 million preferred equity investment in the property with a mandatory redemption date of December 2026. The Company's share, net of unamortized discounts, is $209.9 million with an aggregate weighted average current yield of 8.91% as of September 30, 2024.

The following table summarizes the investments in unconsolidated joint ventures sold during the nine months ended September 30, 2024:


Property	Ownership Interest Sold	Disposition Date	Gross Asset Valuation (in millions)		Gain (Loss) on Sale (in millions) (1) (2)
717 Fifth Avenue	10.92%	January 2024	$	963.0	$	24.9
625 Madison Avenue (3)	90.43%	May 2024	634.6		(7.6)

(1)Represents the Company's share of the gain.

(2)For the nine months ended September 30, 2024, the gain (loss) on sale is net of $7.8 million of employee compensation recognized in connection with the realization of the investment dispositions. Additionally, amounts do not include adjustments for expenses recorded in subsequent periods.

(3)In connection with the sale of the fee ownership interest, the Company, together with its joint venture partner, originated a $235.4 million preferred equity investment in the property with a mandatory redemption date of December 2026. The Company's share, net of unamortized discounts, is $209.9 million with an aggregate weighted average current yield of 8.91% as of September 30, 2024. Prior to the completion of the sale, the Company recorded a charge of $5.9 million for capital contributions required during the three months ended March 31, 2024 while the investment was under contract, which is included in Depreciable real estate reserves and impairments in the consolidated statements of operations.

Schedule of Mortgage Notes and Other Loans Payable Collateralized by the Respective Joint Venture Properties and Assignment of Leases

The mortgage notes and other loans payable collateralized by the respective joint venture properties and assignment of leases as of September 30, 2024 and December 31, 2023, respectively, are as follows (dollars in thousands):


							Principal Outstanding				Principal Outstanding
	Economic		Current Maturity	Final Maturity	Interest		September 30, 2024				December 31, 2023
Property	Interest (1)		Date	Date (2)	Rate (3)		Gross		SLG Share		Gross		SLG Share
Fixed Rate Debt:
650 Fifth Avenue (4)	50.00	%	February 2025	July 2025		5.45%	$	65,000	$	32,500	$	65,000	$	32,500
1515 Broadway	56.87	%	March 2025	March 2025		3.93%	746,330		424,431		762,002		433,344
115 Spring Street (4)	51.00	%	March 2025	March 2025		5.50%	65,550		33,431		65,550		33,431
450 Park Avenue	25.10	%	June 2025	June 2027		6.10%	282,789		70,980		271,394		68,120
11 Madison Avenue	60.00	%	September 2025	September 2025		3.84%	1,400,000		840,000		1,400,000		840,000
One Madison Avenue (5)	25.50	%	November 2025	November 2026		7.10%	625,567		159,520		733,103		186,941
15 Beekman	20.00	%	January 2026	January 2028		5.99%	120,000		24,000		—		—
800 Third Avenue	60.52	%	February 2026	February 2026		3.37%	177,000		107,120		177,000		107,120
919 Third Avenue	51.00	%	April 2026	April 2028		6.11%	500,000		255,000		500,000		255,000
280 Park Avenue	50.00	%	September 2026	September 2028		5.84%	1,075,000		537,500		—		—
245 Park Avenue	50.10	%	June 2027	June 2027		4.30%	1,768,000		885,768		1,768,000		885,768
Worldwide Plaza (4)	24.95	%	November 2027	November 2027		3.98%	1,200,000		299,400		1,200,000		299,400
220 East 42nd Street	51.00	%	December 2027	December 2027		6.77%	496,412		253,170		505,412		257,760
One Vanderbilt Avenue	71.01	%	July 2031	July 2031		2.95%	3,000,000		2,130,300		3,000,000		2,130,300
5 Times Square (4)							—		—		477,783		150,740
625 Madison Avenue							—		—		199,987		180,848
10 East 53rd Street							—		—		220,000		121,000
717 Fifth Avenue							—		—		655,328		71,536
Total fixed rate debt							$	11,521,648	$	6,053,120	$	12,000,559	$	6,053,808
Floating Rate Debt:
11 West 34th Street (4)	30.00	%	February 2023 (6)	February 2023 (6)	L+	1.45%	$	23,000	$	6,900	$	23,000	$	6,900
1552 Broadway (4)	50.00	%	February 2024 (7)	February 2024 (7)	S+	2.75%	193,133		96,566		193,133		96,567
650 Fifth Avenue (4)	50.00	%	February 2025	July 2025	S+	2.25%	210,000		105,000		210,000		105,000
5 Times Square (4)	31.55	%	September 2024 (8)	September 2026 (8)	S+	4.71%	1,163,451		367,069		610,010		192,458
100 Park Avenue	49.90	%	December 2024	December 2025	S+	2.36%	360,000		179,640		360,000		179,640
One Madison Avenue (5)	25.50	%	November 2025	November 2026	S+	3.10%	267,143		68,121		—		—
280 Park Avenue							—		—		1,200,000		600,000
2 Herald Square							—		—		182,500		93,075
15 Beekman							—		—		124,137		24,827
Total floating rate debt							$	2,216,727	$	823,296	$	2,902,780	$	1,298,467
Total joint venture mortgages and other loans payable							$	13,738,375	$	6,876,416	$	14,903,339	$	7,352,275
Deferred financing costs, net							(85,064)		(47,397)		(104,062)		(54,865)
Total joint venture mortgages and other loans payable, net							$	13,653,311	$	6,829,019	$	14,799,277	$	7,297,410

(1)Economic interest represents the Company's interests in the joint venture as of September 30, 2024. Changes in ownership or economic interests, if any, within the current year are disclosed in the notes to the investment in unconsolidated joint ventures table above.

(2)Reflects exercise of all available extension options. The ability to exercise extension options may be subject to certain conditions, including the operating performance of the property.

(3)Interest rates as of September 30, 2024, taking into account interest rate hedges at the joint venture. Corporate interest rate hedges are not taken into consideration. Floating rate debt is presented with the stated spread over Term SOFR ("S").

(4)Included in the Company's alternative strategy portfolio.

(5)The loan is a $1.25 billion construction facility with an initial term of five years with one, one year extension option. Advances under the loan are subject to costs incurred. In conjunction with the loan, the Company provided partial guarantees for interest and principal payments, the amounts of which are based on certain construction milestones and operating metrics.

(6)The Company's joint venture partner is in discussions with the lender on resolution of the past maturity.

(7)The Company is in discussions with the lender on resolution of the past maturity.

(8)The joint venture has agreed to cooperate with the lender on the past due maturity.

Schedule of Combined Balance Sheets for the Unconsolidated Joint Ventures

The combined balance sheets for the unconsolidated joint ventures, at September 30, 2024 and December 31, 2023 are as follows (in thousands):


	September 30, 2024		December 31, 2023
Assets (1)
Commercial real estate property, net	$	16,534,399	$	17,561,406
Cash and restricted cash	696,010		656,038
Tenant and other receivables and deferred rents receivable	643,310		673,532
Debt and preferred equity investments, net	231,080		—
Right-of-use assets	925,461		905,934
Other assets	2,452,064		2,584,765
Total assets	$	21,482,324	$	22,381,675
Liabilities and equity (1)
Mortgages and other loans payable, net	$	13,653,311	$	14,799,277
Deferred revenue	1,011,333		1,108,180
Lease liabilities	1,011,261		990,276
Other liabilities	499,409		447,705
Equity	5,307,010		5,036,237
Total liabilities and equity	$	21,482,324	$	22,381,675
Company's investments in unconsolidated joint ventures	$	2,871,683	$	2,983,313

(1)At September 30, 2024, $544.1 million of net unamortized basis differences between the carrying value of our investments and our share of equity in net assets of the underlying property will be amortized through equity in net income (loss) from unconsolidated joint ventures over the remaining life of the underlying items having given rise to the differences.

Schedule of Combined Statements of Income for the Unconsolidated Joint Ventures

The combined statements of operations for the unconsolidated joint ventures, from acquisition date through the three and nine months ended September 30, 2024 and 2023, are as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Total revenues	$	376,949	$	407,148	$	1,107,295	$	1,140,889
Operating expenses	67,104		63,081		192,587		183,825
Real estate taxes	73,686		78,564		222,797		210,428
Operating lease rent	8,487		7,307		25,990		21,746
Interest expense, net of interest income	141,067		162,897		433,117		421,528
Amortization of deferred financing costs	4,487		6,897		14,718		21,140

Depreciation and amortization	137,640		138,199		407,429		380,867
Total expenses	432,471		456,945		1,296,638		1,239,534
Gain on early extinguishment of debt	—		—		233,704		—
Net (loss) income before gain (loss) on sale	$	(55,522)	$	(49,797)	$	44,361	$	(98,645)
Company's equity in net (loss) income from unconsolidated joint ventures	$	(15,428)	$	(15,126)	$	100,057	$	(44,470)

Significant Accounting Policies - Schedule of Identified Intangible Assets and Intangible Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Identified intangible assets (included in other assets):
Gross amount	$ 273,010	$ 189,680
Accumulated amortization	(193,327)	(184,902)
Net	79,683	4,778
Identified intangible liabilities (included in deferred revenue):
Gross amount	226,034	205,394
Accumulated amortization	(203,459)	(202,089)
Net	$ 22,575	$ 3,305

Segment Information - Additional Information (Details)
$ in Thousands

3 Months Ended

9 Months Ended

Sep. 30, 2024

USD ($)

Sep. 30, 2023

USD ($)

Sep. 30, 2024

USD ($)

segment

Sep. 30, 2023

USD ($)

Dec. 31, 2023

USD ($)

Segment information

Number of reportable segments | segment

Total revenues

$ 229,691

$ 210,186

$ 640,393

$ 701,986

Net income (loss)

(9,264)

(21,694)

11,084

(439,279)

Total assets

^[1]

10,216,072

$ 9,531,181

Marketing, general and administrative

21,015

22,873

62,360

69,132

Operating Segments | Real Estate Segment

Segment information

Total revenues

183,139

165,428

522,041

591,117

Net income (loss)

(18,326)

(20,385)

(11,745)

(444,904)

Total assets

8,707,930

8,707,147

Operating Segments | SUMMIT Segment

Segment information

Total revenues

36,437

35,069

94,643

83,020

Net income (loss)

(362)

(1,897)

11,202

(1,101)

Total assets

478,288

464,799

Operating Segments | Debt and Preferred Equity Segment

Segment information

Total revenues

10,115

9,689

23,709

27,849

Net income (loss)

9,424

$ 588

11,627

$ 6,726

Total assets

$ 1,029,854

$ 359,235

[1]

Lease Income

9 Months Ended

Sep. 30, 2024

Leases [Abstract]

Lease Income

The Operating Partnership is the lessor and the sublessor to tenants under operating and sales-type leases. The minimum rental amounts due under the leases are generally subject to scheduled fixed increases or adjustments. The leases generally also require that the tenants reimburse us for increases in certain operating costs and real estate taxes above their base year costs.

The components of lease income from operating leases in our consolidated statements of operations during the three and nine months ended September 30, 2024 and 2023 were as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Fixed lease payments	$	140,450	$	131,664	$	405,130	$	457,454
Variable lease payments	17,317		19,467		45,687		60,211
Total lease payments (1)	$	157,767	$	151,131	$	450,817	$	517,665
Amortization of acquired above and below-market leases	(834)		(140)		(1,748)		14,313
Total rental revenue	$	156,933	$	150,991	$	449,069	$	531,978

(1)Amounts include $47.4 million and $141.6 million of sublease income during the three and nine months ended September 30, 2024, respectively, and $49.7 million and $147.4 million of sublease income during the three and nine months ended September 30, 2023, respectively.

The components of lease income from sales-type leases during the three and nine months ended September 30, 2024 and 2023 were as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023

Interest income (1)	$	1,127	$	1,113	$	3,369	$	3,328

(1)These amounts are included in Interest expense, net of interest income in our consolidated statements of operations.

Lease Income

The components of lease income from operating leases in our consolidated statements of operations during the three and nine months ended September 30, 2024 and 2023 were as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Fixed lease payments	$	140,450	$	131,664	$	405,130	$	457,454
Variable lease payments	17,317		19,467		45,687		60,211
Total lease payments (1)	$	157,767	$	151,131	$	450,817	$	517,665
Amortization of acquired above and below-market leases	(834)		(140)		(1,748)		14,313
Total rental revenue	$	156,933	$	150,991	$	449,069	$	531,978

The components of lease income from sales-type leases during the three and nine months ended September 30, 2024 and 2023 were as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023

Interest income (1)	$	1,127	$	1,113	$	3,369	$	3,328

(1)These amounts are included in Interest expense, net of interest income in our consolidated statements of operations.

Properties Held for Sale and Property Dispositions (Tables)

9 Months Ended

Sep. 30, 2024

Discontinued Operations and Disposal Groups [Abstract]

Summary of properties sold

The following table summarizes the properties sold during the nine months ended September 30, 2024:


Property	Disposition Date	Property Type	Unaudited Approximate Usable Square Feet	Sales Price (1) (in millions)		(Loss) Gain on Sale (in millions) (2)
719 Seventh Avenue	June 2024	Fee Interest	10,040	$	30.5	$	(2.0)
Palisades Premier Conference Center	July 2024	Fee Interest	450,000	26.3		$	7.3

(1)Sales price represents the gross sales price for a property or the gross asset valuation for interests in a property.

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-SubTopic 10
-Topic 360
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-3

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483475/205-20-45-11

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-3A

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-4A

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-5A

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-5B

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5D
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-5D

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-7

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-3A

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 20
-Topic 205
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-1

Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-3

+ Details

Noncontrolling Interests on the Company's Consolidated Financial Statements

9 Months Ended

Sep. 30, 2024

Noncontrolling Interest [Abstract]

Noncontrolling Interests on the Company's Consolidated Financial Statements

Noncontrolling interests represent the common and preferred units of limited partnership interest in the Operating Partnership not held by the Company as well as third party equity interests in our other consolidated subsidiaries. Noncontrolling interests in the Operating Partnership are shown in the mezzanine equity while the noncontrolling interests in our other consolidated subsidiaries are shown in the equity section of the Company’s consolidated financial statements.

Common Units of Limited Partnership Interest in the Operating Partnership

As of September 30, 2024 and December 31, 2023, the noncontrolling interest unit holders owned 6.42%, or 4,474,406 units, and 5.75%, or 3,949,448 units, of the Operating Partnership, respectively. As of September 30, 2024, 4,474,406 shares of our common stock were reserved for issuance upon the redemption of units of limited partnership interest of the Operating Partnership.

Noncontrolling interests in the Operating Partnership is recorded at the greater of its cost basis or fair market value based on the closing stock price of our common stock at the end of the reporting period.

Below is a summary of the activity relating to the noncontrolling interests in the Operating Partnership for the nine months ended September 30, 2024 and the twelve months ended December 31, 2023 (in thousands):


	September 30, 2024		December 31, 2023
Balance at beginning of period	$	238,051	$	269,993
Distributions	(10,545)		(14,779)
Issuance of common units	13,927		25,365
Redemption and conversion of common units	(21,977)		(18,589)
Net income (loss)	(166)		(37,465)
Accumulated other comprehensive income (loss) allocation	(3,097)		(1,960)
Fair value adjustment	77,400		15,486
Balance at end of period	$	293,593	$	238,051

Preferred Units of Limited Partnership Interest in the Operating Partnership

Below is a summary of the preferred units of limited partnership interest in the Operating Partnership as of September 30, 2024:


Issuance	Stated Distribution Rate		Number of Units Authorized	Number of Units Issued	Number of Units Outstanding	Annual Dividend Per Unit(1)		Liquidation Preference Per Unit(2)		Conversion Price Per Unit(3)		Date of Issuance
Series A (4)	6.00	%	109,161	109,161	109,161	$	60.0000	$	1,000.00	$	—	August 2015
Series F	7.00	%	60	60	60	70.0000		1,000.00		29.12		January 2007
Series K	3.50	%	700,000	563,954	341,677	0.8750		25.00		134.67		August 2014
Series L	4.00	%	500,000	378,634	372,634	1.0000		25.00		—		August 2014
Series R	3.50	%	400,000	400,000	400,000	0.8750		25.00		154.89		August 2015
Series S	4.00	%	1,077,280	1,077,280	1,077,280	1.0000		25.00		—		August 2015
Series V (5)	5.00	%	40,000	40,000	40,000	1.2500		25.00		—		May 2019
Series W (6)	(6)		1	1	1	(6)		(6)		(6)		January 2020

(1)Dividends are cumulative, subject to certain provisions.

(2)Units are redeemable at any time at par for cash at the option of the unit holder unless otherwise specified.

(3)If applicable, units are convertible into a number of common units of limited partnership interest in the Operating Partnership equal to (i) the liquidation preference plus accumulated and unpaid distributions on the conversion date divided by (ii) the amount shown in the table.

(4)Issued through a consolidated subsidiary. The units are redeemable at any time after December 13, 2024 at par for cash at the option of the unit holder.

(5)The Series V Preferred Units are redeemable at any time after January 1, 2025 at par for cash at the option of the unit holder.

(6)The Series W preferred unit was issued in January 2020 in exchange for the then-outstanding Series O preferred unit. The holder of the Series W preferred unit is entitled to quarterly dividends in an amount calculated as (i) 1,350 multiplied by (ii) the current distribution per common unit of limited partnership in SL Green Operating Partnership. The holder has the right to require the Operating Partnership to repurchase the Series W unit for cash, or convert the Series W unit for Class B units, in each case at a price that is determined based on the closing price of the Company's common stock at the time such right is exercised. The unit's liquidation preference is the fair market value of the unit plus accrued distributions at the time of a liquidation event.

Below is a summary of the activity relating to the preferred units in the Operating Partnership for the nine months ended September 30, 2024 and the twelve months ended December 31, 2023 (in thousands):


	September 30, 2024		December 31, 2023
Balance at beginning of period	$	166,501	$	177,943
Issuance of preferred units	—		—
Redemption of preferred units	—		(11,700)
Dividends paid on preferred units	(3,916)		(6,271)
Accrued dividends on preferred units	4,146		6,529
Balance at end of period	$	166,731	$	166,501

Consolidated Statements of Operations (Partnership) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues
Rental revenue, net	$ 156,933	$ 150,991	$ 449,069	$ 531,978
SUMMIT Operator revenue	36,437	35,069	94,643	83,020
Investment income	5,344	9,689	18,938	27,849
Interest income from real estate loans held by consolidated securitization vehicles	4,771	0	4,771	0
Other income	26,206	14,437	72,972	59,139
Total revenues	229,691	210,186	640,393	701,986
Expenses
Operating expenses	49,507	49,585	139,448	148,606
Real estate taxes	30,831	31,195	94,495	112,463
Operating lease rent	6,363	7,253	19,136	20,209
SUMMIT Operator expenses	37,901	32,801	82,947	76,324
Interest expense, net of interest income	42,091	27,440	109,067	109,714
Amortization of deferred financing costs	1,669	2,152	4,885	6,327
SUMMIT Operator tax (benefit) expense	(1,779)	3,735	(1,219)	6,881
Interest expense on senior obligations of consolidated securitization vehicles	3,330	0	3,330	0
Depreciation and amortization	53,176	50,642	154,007	198,760
Loan loss and other investment reserves, net of recoveries	0	0	0	6,890
Transaction related costs	171	166	263	1,083
Marketing, general and administrative	21,015	22,873	62,360	69,132
Total expenses	244,275	227,842	668,719	756,389
Equity in net (loss) income from unconsolidated joint ventures	(15,428)	(15,126)	100,057	(44,470)
Equity in net gain (loss) on sale of interest in unconsolidated joint venture/real estate	371	0	19,006	(79)
Purchase price and other fair value adjustments	12,906	10,183	(36,321)	(6,987)
Gain (loss) on sale of real estate, net	7,471	516	4,730	(27,813)
Depreciable real estate reserves and impairment	0	389	(65,839)	(305,527)
Gain on early extinguishment of debt	0	0	17,777	0
Net (loss) income	(9,264)	(21,694)	11,084	(439,279)
Net loss attributable to noncontrolling interests:
Noncontrolling interests in other partnerships	(985)	(1,794)	(4,150)	(4,459)
Preferred units distributions	(2,176)	(1,903)	(6,485)	(5,352)
Net (loss) income attributable to SL Green	(9,541)	(20,229)	8,915	(412,679)
Perpetual preferred unit dividends	(3,738)	(3,738)	(11,213)	(11,213)
SL Green Operating Partnership
Revenues
Rental revenue, net	156,933	150,991	449,069	531,978
SUMMIT Operator revenue	36,437	35,069	94,643	83,020
Investment income	5,344	9,689	18,938	27,849
Interest income from real estate loans held by consolidated securitization vehicles	4,771	0	4,771	0
Other income	26,206	14,437	72,972	59,139
Total revenues	229,691	210,186	640,393	701,986
Expenses
Operating expenses	49,507	49,585	139,448	148,606
Real estate taxes	30,831	31,195	94,495	112,463
Operating lease rent	6,363	7,253	19,136	20,209
SUMMIT Operator expenses	37,901	32,801	82,947	76,324
Interest expense, net of interest income	42,091	27,440	109,067	109,714
Amortization of deferred financing costs	1,669	2,152	4,885	6,327
SUMMIT Operator tax (benefit) expense	(1,779)	3,735	(1,219)	6,881
Interest expense on senior obligations of consolidated securitization vehicles	3,330	0	3,330	0
Depreciation and amortization	53,176	50,642	154,007	198,760
Loan loss and other investment reserves, net of recoveries	0	0	0	6,890
Transaction related costs	171	166	263	1,083
Marketing, general and administrative	21,015	22,873	62,360	69,132
Total expenses	244,275	227,842	668,719	756,389
Equity in net (loss) income from unconsolidated joint ventures	(15,428)	(15,126)	100,057	(44,470)
Equity in net gain (loss) on sale of interest in unconsolidated joint venture/real estate	371	0	19,006	(79)
Purchase price and other fair value adjustments	12,906	10,183	(36,321)	(6,987)
Gain (loss) on sale of real estate, net	7,471	516	4,730	(27,813)
Depreciable real estate reserves and impairment	0	389	(65,839)	(305,527)
Gain on early extinguishment of debt	0	0	17,777	0
Net (loss) income	(9,264)	(21,694)	11,084	(439,279)
Net loss attributable to noncontrolling interests:
Noncontrolling interests in other partnerships	(985)	1,794	4,150	4,459
Preferred units distributions	(2,176)	(1,903)	(6,485)	(5,352)
Net (loss) income attributable to SL Green	(10,455)	(21,803)	8,749	(440,172)
Perpetual preferred unit dividends	(3,738)	(3,738)	(11,213)	(11,213)
Net loss attributable to SLGOP common unitholders	$ (14,193)	$ (25,541)	$ (2,464)	$ (451,385)
Basic loss per unit (in dollars per share)	$ (0.23)	$ (0.38)	$ (0.09)	$ (6.63)
Diluted loss per unit (in dollars per share)	$ (0.23)	$ (0.38)	$ (0.09)	$ (6.63)
Basic weighted average common units outstanding (in shares)	67,999	68,296	68,092	68,274
Diluted weighted average common units and common unit equivalents outstanding (in shares)	67,999	68,296	68,092	68,274

Share-based Compensation

9 Months Ended

Sep. 30, 2024

Share-Based Payment Arrangement [Abstract]

Share-based Compensation

We have share-based employee and director compensation plans. Our employees are compensated through the Operating Partnership. Under each plan, whenever the Company issues common or preferred stock, the Operating Partnership issues an equivalent number of units of limited partnership interest of a corresponding class to the Company.

The Fifth Amended and Restated 2005 Stock Option and Incentive Plan, or the 2005 Plan, was approved by the Company's Board of Directors in April 2022 and its stockholders in June 2022 at the Company's annual meeting of stockholders. The 2005 Plan authorizes the issuance of stock options, stock appreciation rights, unrestricted and restricted stock, phantom shares, dividend equivalent rights, cash-based awards and other equity-based awards. Subject to adjustments upon certain corporate transactions or events, awards with respect to up to a maximum of 32,210,000 fungible units may be granted under the 2005 Plan. Currently, different types of awards count against the limit on the number of fungible units differently, with (1) full-value awards (i.e., those that deliver the full value of the award upon vesting, such as restricted stock) counting as 2.59 Fungible Units per share subject to such awards, (2) stock options, stock appreciation rights and other awards that do not deliver full value and expire five years from the date of grant counting as 0.84 fungible units per share subject to such awards, and (3) all other awards (e.g., 10-year stock options) counting as 1.0 fungible units per share subject to such awards. Awards granted under the 2005 Plan prior to the approval of the fifth amendment and restatement in June 2022 continue to count against the fungible unit limit based on the ratios that were in effect at the time such awards were granted, which may be different than the current ratios. As a result, depending on the types of awards issued, the 2005 Plan may result in the issuance of more or less than 32,210,000 shares. If a stock option or other award granted under the 2005 Plan expires or terminates, the common stock subject to any portion of the award that expires or terminates without having been exercised or paid, as the case may be, will again become available for the issuance of additional awards. Shares of our common stock distributed under the 2005 Plan may be treasury shares or authorized but unissued shares. Currently, unless the 2005 Plan has been previously terminated by the Company's Board of Directors, new awards may be granted under the 2005 Plan until June 1, 2032, which is the tenth anniversary of the date that the 2005 Plan was most recently approved by the Company's stockholders. As of September 30, 2024, 3.5 million fungible units were available for issuance under the 2005 Plan after reserving for shares underlying outstanding restricted stock units, phantom stock units granted pursuant to our Non-Employee Directors' Deferral Program and LTIP Units.

Stock Options and Class O LTIP Units

Options are granted with an exercise price at the fair market value of the Company's common stock on the date of grant and, subject to employment, generally expire five years or ten years from the date of grant, are not transferable other than on death, and generally vest in one year to five years commencing one year from the date of grant. We have also granted Class O LTIP Units, which are a class of LTIP Units in the Operating Partnership structured to provide economics similar to those of stock options. Class O LTIP Units, once vested, may be converted, at the election of the holder, into a number of common units of the Operating Partnership per Class O LTIP Unit determined by the increase in value of a share of the Company’s common stock at the time of conversion over a participation threshold, which equals the fair market value of a share of the Company’s common stock at the time of grant. Class O LTIP Units are entitled to distributions, subject to vesting, equal per unit to 10% of the per unit distributions paid with respect to the common units of the Operating Partnership.

The fair value of each stock option or LTIP Unit granted is estimated on the date of grant using the Black-Scholes option pricing model based on historical information. There were no options granted during the nine months ended September 30, 2024 or the year ended December 31, 2023.

A summary of the status of the Company's stock options as of September 30, 2024 and December 31, 2023, and changes during the nine months ended September 30, 2024 and year ended December 31, 2023 are as follows:


	September 30, 2024			December 31, 2023
	Options Outstanding	Weighted Average Exercise Price		Options Outstanding	Weighted Average Exercise Price
Balance at beginning of period	115,980	$	103.52	313,480	$	97.59

Exercised	—	—		—	—
Lapsed or canceled	—	—		(197,500)	84.14
Balance at end of period	115,980	$	103.52	115,980	$	103.52
Options exercisable at end of period	115,980	$	103.52	115,980	$	103.52

The remaining weighted average contractual life of the options outstanding was 2.2 years and the remaining average contractual life of the options exercisable was 2.2 years.

During the three and nine months ended September 30, 2024, we recognized no compensation expense related to options. During the three and nine months ended September 30, 2023, we recognized no compensation expense related to options. As of September 30, 2024, there was no unrecognized compensation cost related to unvested stock options.

Restricted Shares

Shares may be granted to certain employees, including our executives, and vesting occurs upon the completion of a service period or our meeting established financial performance criteria. Vesting occurs at rates ranging from 15% to 35% once performance criteria are reached.

A summary of the Company's restricted stock as of September 30, 2024 and December 31, 2023 and changes during the nine months ended September 30, 2024 and the year ended December 31, 2023, are as follows:


	September 30, 2024		December 31, 2023
Balance at beginning of period	4,089,174		3,758,174
Granted	7,734		337,350
Canceled	(10,050)		(6,350)
Balance at end of period	4,086,858		4,089,174
Vested during the period	136,120		147,915
Compensation expense recorded	$	7,935,369	$	7,766,055
Total fair value of restricted stock granted during the period	$	394,851	$	15,789,540

The fair value of restricted stock that vested during the nine months ended September 30, 2024 and the year ended December 31, 2023 was $7.1 million and $10.2 million, respectively. As of September 30, 2024, there was $12.2 million of total unrecognized compensation cost related to restricted stock, which is expected to be recognized over a weighted average period of 2.0 years.

We granted LTIP Units, which include bonus, time-based and performance-based awards, with a fair value of $23.6 million and $38.1 million as of September 30, 2024 and December 31, 2023, respectively. The grant date fair value of the LTIP Unit awards was calculated in accordance with ASC 718. A third-party consultant determined that the fair value of the LTIP Units has a discount to our common stock price. The discount was calculated by considering the inherent uncertainty that the LTIP Units will reach parity with other common partnership units and the illiquidity due to transfer restrictions. As of September 30, 2024, there was $28.5 million of total unrecognized compensation expense related to the time-based and performance-based awards, which is expected to be recognized over a weighted average period of 1.6 years.

During the three and nine months ended September 30, 2024, we recorded compensation expense related to bonus, time-based and performance-based awards of $6.7 million and $19.7 million. During the three and nine months ended September 30, 2023, we recorded compensation expense related to bonus, time-based and performance-based awards of $10.6 million and $31.2 million, respectively.

For the three and nine months ended September 30, 2024, $0.4 million and $1.3 million, respectively, was capitalized to assets associated with compensation expense related to our long-term compensation plans, restricted stock and stock options. For the three and nine months ended September 30, 2023, $0.3 million and $1.0 million, respectively, was capitalized to assets associated with compensation expense related to our long-term compensation plans, restricted stock and stock options.

Deferred Compensation Plan for Directors

Under our Non-Employee Director's Deferral Program, which commenced July 2004, the Company's non-employee directors may elect to defer up to 100% of their annual retainer fee, chairman fees, meeting fees and annual stock grant. Unless otherwise elected by a participant, fees deferred under the program shall be credited in the form of phantom stock units. The program provides that a director's phantom stock units generally will be settled in an equal number of shares of common stock upon the earlier of (i) the January 1 coincident with or the next following such director's termination of service from the Board of Directors or (ii) a change in control by us, as defined by the program. Phantom stock units are credited to each non-employee director quarterly using the closing price of our common stock on the first business day of the respective quarter. Each participating non-employee director is also credited with dividend equivalents or phantom stock units based on the dividend rate for each quarter, which are either paid in cash currently or credited to the director’s account as additional phantom stock units.

During the nine months ended September 30, 2024, 15,945 phantom stock units and 25,590 shares of common stock were issued to our Board of Directors. We recorded compensation expense of $0.2 million and $2.6 million during the three and nine months ended September 30, 2024, respectively, related to the Deferred Compensation Plan. We recorded compensation expense of $0.2 million and $2.5 million during the three and nine months ended September 30, 2023, respectively, related to the Deferred Compensation Plan.

As of September 30, 2024, there were 125,654 phantom stock units outstanding pursuant to our Non-Employee Director's Deferral Program.

Employee Stock Purchase Plan

In 2007, the Company's Board of Directors adopted the 2008 Employee Stock Purchase Plan, or ESPP, to provide equity-based incentives to eligible employees. The ESPP is intended to qualify as an "employee stock purchase plan" under Section 423 of the Code, and has been adopted by the board to enable our eligible employees to purchase the Company's shares of common stock through payroll deductions. The ESPP became effective on January 1, 2008 with a maximum of 500,000 shares of the common stock available for issuance, subject to adjustment upon a merger, reorganization, stock split or other similar corporate change. The Company filed a registration statement on Form S-8 with the SEC with respect to the ESPP. The common stock is offered for purchase through a series of successive offering periods. Each offering period will be three months in duration and will begin on the first day of each calendar quarter, with the first offering period having commenced on January 1, 2008. The ESPP provides for eligible employees to purchase the common stock at a purchase price equal to 85% of the lesser of (1) the market value of the common stock on the first day of the offering period or (2) the market value of the common stock on the last day of the offering period. The ESPP was approved by our stockholders at our 2008 annual meeting of stockholders. As of September 30, 2024, 241,790 shares of our common stock had been issued under the ESPP.

Related Party Transactions (Tables)

9 Months Ended

Sep. 30, 2024

Schedule of Amounts Due from/to Related Parties

Amounts due from joint ventures, inclusive of our ownership share of the joint ventures, and related parties as of September 30, 2024 and December 31, 2023 consisted of the following (in thousands):


	September 30, 2024		December 31, 2023
Due from joint ventures	$	7,276	$	10,603
Other	5,801		1,565
Related party receivables	$	13,077	$	12,168

Debt and Preferred Equity Investments

9 Months Ended

Sep. 30, 2024

Investments, Debt and Equity Securities [Abstract]

Debt and Preferred Equity Investments

Below is a summary of the activity in our consolidated debt and preferred equity investments for the nine months ended September 30, 2024 and the twelve months ended December 31, 2023 (in thousands):


	September 30, 2024		December 31, 2023
Balance at beginning of year (1)	$	346,745	$	623,280
Debt investment originations/fundings/accretion (2)	5,334		72,160
Preferred equity investment originations/accretion (2) (3)	6,474		8,142
Redemptions/sales/syndications/equity ownership/amortization	(64,629)		(349,947)
Net change in loan loss reserves	—		(6,890)
Balance at end of period (1) (4)	$	293,924	$	346,745

(1)Net of unamortized fees, discounts, and premiums.

(2)Accretion includes amortization of fees and discounts and paid-in-kind investment income.

(3)Excludes a $209.9 million preferred equity investment that is included in Investment in unconsolidated joint ventures in our consolidated balance sheet. See Note 6, "Investments in Unconsolidated Joint Ventures."

(4)Includes two investments with a total carrying value of $49.8 million that are included in the Company's alternative strategy portfolio.

Below is a summary of our consolidated debt and preferred equity investments as of September 30, 2024 (dollars in thousands):


	Floating Rate					Fixed Rate					Total Carrying Value			Senior Financing		Maturity (2)
Type	Carrying Value		Face Value		Interest Rate (1)	Carrying Value		Face Value		Interest Rate


Mezzanine Debt	$	109,450	$	109,604	S + 5.00% - 12.11%	$	50,000	$	50,000	8.00% - 8.40%	$	159,450	(3)	$	804,021	2024 - 2029
Preferred Equity (4)	—		—		—	134,474		134,474		6.5%	134,474			250,000		2027
Balance at end of period	$	109,450	$	109,604		$	184,474	$	184,474		$	293,924		$	1,054,021

(1)Floating interest rates are presented with the stated spread over Term SOFR ("S").

(2)Excludes available extension options to the extent they have not been exercised as of the date of this filing.

(3)Includes two investments with a total carrying value of $49.8 million that are included in the Company's alternative strategy portfolio.

(4)Excludes a $209.9 million preferred equity investment that is included in Investment in unconsolidated joint ventures in our consolidated balance sheet. See Note 6, "Investments in Unconsolidated Joint Ventures."

The following table is a roll forward of our total allowance for loan losses for the nine months ended September 30, 2024 and the twelve months ended December 31, 2023 (in thousands):


	September 30, 2024		December 31, 2023
Balance at beginning of year	$	13,520	$	6,630



Current period provision for loan loss	—		6,890

Balance at end of period (1)	$	13,520	$	13,520

(1)As of September 30, 2024, all debt and preferred equity investments on non-accrual had an allowance for loan loss except for one debt investment with a carrying value of $49.8 million, which is included in the Company's alternative strategy portfolio.

As of September 30, 2024, two investments that are in the Company's alternative strategy portfolio and have a total carrying value, net of reserves, of $49.8 million were not performing in accordance with their respective terms. As of December 31, 2023, the same two investments with a total carrying value, net of reserves, of $49.8 million were not performing in accordance with their respective terms. This is further discussed in the Debt Investments and Preferred Equity Investments tables below.

No other financing receivables were 90 days past due as of September 30, 2024 and December 31, 2023.

The following table sets forth the carrying value of our consolidated debt and preferred equity investment portfolio by risk rating as of September 30, 2024 and December 31, 2023 (dollars in thousands):


Risk Rating	September 30, 2024		December 31, 2023
1 - Low Risk Assets - Low probability of loss	$	154,474	$	210,333
2 - Watch List Assets - Higher potential for loss (1)	139,450		136,412
3 - High Risk Assets - Loss more likely than not	—		—
	$	293,924	$	346,745

(1)Includes two investments with a total carrying value of $49.8 million that are included in the Company's alternative strategy portfolio.

The following table sets forth the carrying value of our consolidated debt and preferred equity investment portfolio by year of origination and risk rating as of September 30, 2024 (dollars in thousands):


	As of September 30, 2024
Risk Rating	2024 (1)		2023 (1)		2022 (1)		Prior (1)			Total
1 - Low Risk Assets - Low probability of loss	$	—	$	—	$	—	$	154,474		$	154,474
2 - Watch List Assets - Higher potential for loss	—		—		—		139,450		(2)	139,450
3 - High Risk Assets - Loss more likely than not	—		—		—		—			—
	$	—	$	—	$	—	$	293,924		$	293,924

(1)Year in which the investment was originated or acquired by us or in which a material modification occurred.

(2)Includes two investments with a total carrying value of $49.8 million that are included in the Company's alternative strategy portfolio.

We have determined that we have one portfolio segment of financing receivables as of September 30, 2024 and December 31, 2023 comprised of commercial real estate which is primarily recorded in debt and preferred equity investments.

Included in Other assets is an additional amount of financing receivables representing loans to joint venture partners totaling $10.9 million and $8.8 million as of September 30, 2024 and December 31, 2023, respectively. The Company recorded no provisions for loan losses related to these financing receivables for the nine months ended September 30, 2024 and 2023. All of these loans have a risk rating of 2 and were performing in accordance with their respective terms.

Debt Investments

As of September 30, 2024 and December 31, 2023, we held the following consolidated debt investments with an aggregate weighted average current yield of 6.32% as of September 30, 2024 (dollars in thousands):


Loan Type	September 30, 2024 Future Funding Obligations		September 30, 2024 Senior Financing		September 30, 2024 Carrying Value (1)		December 31, 2023 Carrying Value (1)		Maturity Date (2)
Fixed Rate Investments:
Mezzanine Loan (3) (4) (6)	$	—	$	105,000	$	13,366	$	13,366	October 2024
Mezzanine Loan	—		95,000		30,000		30,000		January 2025
Mezzanine Loan	—		85,000		20,000		20,000		December 2029
Total fixed rate	$	—	$	285,000	$	63,366	$	63,366
Floating Rate Investments:
Mezzanine Loan (5) (6)	$	—	$	275,000	$	50,000	$	50,000	April 2023
Mezzanine Loan	—		54,000		8,620		8,243		January 2025
Mezzanine Loan	8,099		190,021		50,984		48,323		January 2026
Mezzanine Loan	—		—		—		62,333		May 2024
Total floating rate	$	8,099	$	519,021	$	109,604	$	168,899
Allowance for loan loss	$	—	$	—	$	(13,520)	$	(13,520)
Total	$	8,099	$	804,021	$	159,450	$	218,745

(1)Carrying value is net of discounts, premiums, original issue discounts and deferred origination fees.

(2)Represents contractual maturity, excluding any extension options to the extent they have not been exercised as of the date of this filing.

(3)Carrying value is net of a $12.0 million participation that was sold and did not meet the conditions for sale accounting. That participation is included in Other assets and Other liabilities on the consolidated balance sheets as a result.

(4)This loan went into default and was put on non-accrual in June 2020 and remains on non-accrual as of September 30, 2024. No investment income has been recognized subsequent to it being put on non-accrual. In the first quarter of 2023, the Company fully reserved the balance of the investment. Additionally, we determined the borrower entity to be a VIE, in which we are not the primary beneficiary.

(5)This loan went into default and was put on non-accrual in January 2023 and remains on non-accrual as of September 30, 2024. No investment income has been recognized subsequent to it being put on non-accrual. The Company is in discussions with the borrower with respect to the loan.

(6)Included in the Company's alternative strategy portfolio.

Preferred Equity Investments

As of September 30, 2024 and December 31, 2023, we held the following consolidated preferred equity investment with an aggregate weighted average current yield of 6.55% as of September 30, 2024 (dollars in thousands), excluding a $209.9 million preferred equity investment that is included in Investment in unconsolidated joint ventures in our consolidated balance sheet:


Type	September 30, 2024 Future Funding Obligations		September 30, 2024 Senior Financing		September 30, 2024 Carrying Value (1)		December 31, 2023 Carrying Value (1)		Mandatory Redemption (2)
Preferred Equity	$	—	$	250,000	$	134,474	$	128,000	February 2027

Allowance for loan loss	$	—	$	—	$	—	$	—
Total	$	—	$	250,000	$	134,474	$	128,000

(1)Carrying value is net of deferred origination fees.

(2)Represents contractual redemption, excluding any unexercised extension options.

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Assets
Debt and preferred equity investments, discount and deferred origination fees	$ 1,618	$ 1,630
Allowance for loan and lease losses, real estate	13,520	13,520
Real estate loans held by consolidated securitization vehicles	586,823	0
Senior obligations of consolidated securitization vehicles	571,711	0
Secured borrowings	$ 237,454	$ 0
Equity
Preferred stock, par value (in dollars per share)	$ 0.01
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	160,000,000	160,000,000
Common stock, shares issued (in shares)	66,295,000	65,786,000
Common stock, shares outstanding (in shares)	66,295,000	65,786,000
Treasury stock, shares (in shares)	1,060,000	1,060,000
Land and land interests	$ 1,134,432	$ 1,092,671
Building and improvements	3,781,403	3,655,624
Building leasehold and improvements	1,374,059	1,354,569
Right-of-use assets	870,782	885,929
Accumulated depreciation	2,084,755	1,968,004
Real estate loans held by consolidated securitization vehicles (includes $586,823 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	713,218	0
Other assets	490,722	413,670
Mortgages and other loans payable, net	1,643,992	1,491,319
Lease liability - financing leases	106,518	105,531
Senior obligations of consolidated securitization vehicles (includes $571,711 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	603,902	0
Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	409,844	471,401
Service Corporation
Equity
Land and land interests	104,100	41,200
Building and improvements	65,400	40,500
Building leasehold and improvements	0	0
Right-of-use assets	0	0
Accumulated depreciation	3,200	5,400
Real estate loans held by consolidated securitization vehicles (includes $586,823 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	713,200	0
Other assets	776,300	676,900
Mortgages and other loans payable, net	204,300	50,000
Accrued interest payable	900	900
Lease liability - financing leases	0	0
Senior obligations of consolidated securitization vehicles (includes $571,711 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	603,900	0
Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	$ 308,000	$ 306,500
Series I Preferred Stock
Equity
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, liquidation preference (in dollars per share)	$ 25.00	$ 25.00
Preferred stock, shares issued (in shares)	9,200,000	9,200,000
Preferred stock, shares outstanding (in shares)	9,200,000	9,200,000

Partners' Capital of the Operating Partnership (Tables)

9 Months Ended

Sep. 30, 2024

Equity [Abstract]

Schedule of Calculation of Numerator and Denominator in Earnings Per Unit

The Operating Partnership's earnings per unit for the three and nine months ended September 30, 2024 and 2023, respectively, are computed as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Numerator	2024		2023		2024		2023
Basic Earnings:
Net loss attributable to SLGOP common unitholders	$	(14,193)	$	(25,541)	$	(2,464)	$	(451,385)
Less: distributed earnings allocated to participating securities	(1,147)		(408)		(3,415)		(1,225)

Net loss attributable to SLGOP common unitholders (numerator for basic earnings per unit)	$	(15,340)	$	(25,949)	$	(5,879)	$	(452,610)


Net loss attributable to SLGOP common unitholders (numerator for diluted earnings per unit)	$	(15,340)	$	(25,949)	$	(5,879)	$	(452,610)


	Three Months Ended September 30,		Nine Months Ended September 30,
Denominator	2024	2023	2024	2023
Basic units:
Weighted average common units outstanding	67,999	68,296	68,092	68,274



Diluted weighted average common units outstanding	67,999	68,296	68,092	68,274

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues
Rental revenue, net	$ 156,933	$ 150,991	$ 449,069	$ 531,978
SUMMIT Operator revenue	36,437	35,069	94,643	83,020
Investment income	5,344	9,689	18,938	27,849
Interest income from real estate loans held by consolidated securitization vehicles	4,771	0	4,771	0
Other income	26,206	14,437	72,972	59,139
Total revenues	229,691	210,186	640,393	701,986
Expenses
Operating expenses, including related party expenses of $0 and $2 in 2024, and $2 and $3 in 2023	49,507	49,585	139,448	148,606
Real estate taxes	30,831	31,195	94,495	112,463
Operating lease rent	6,363	7,253	19,136	20,209
SUMMIT Operator expenses	37,901	32,801	82,947	76,324
Interest expense, net of interest income	42,091	27,440	109,067	109,714
Amortization of deferred financing costs	1,669	2,152	4,885	6,327
SUMMIT Operator tax (benefit) expense	(1,779)	3,735	(1,219)	6,881
Interest expense on senior obligations of consolidated securitization vehicles	3,330	0	3,330	0
Depreciation and amortization	53,176	50,642	154,007	198,760
Loan loss and other investment reserves, net of recoveries	0	0	0	6,890
Transaction related costs	171	166	263	1,083
Marketing, general and administrative	21,015	22,873	62,360	69,132
Total expenses	244,275	227,842	668,719	756,389
Equity in net (loss) income from unconsolidated joint ventures	(15,428)	(15,126)	100,057	(44,470)
Equity in net gain (loss) on sale of interest in unconsolidated joint venture/real estate	371	0	19,006	(79)
Purchase price and other fair value adjustments	12,906	10,183	(36,321)	(6,987)
Gain (loss) on sale of real estate, net	7,471	516	4,730	(27,813)
Depreciable real estate reserves and impairment	0	389	(65,839)	(305,527)
Gain on early extinguishment of debt	0	0	17,777	0
Net (loss) income	(9,264)	(21,694)	11,084	(439,279)
Net loss attributable to noncontrolling interests:
Noncontrolling interests in the Operating Partnership		1,574	166	27,493
Noncontrolling interests in other partnerships	985	1,794	4,150	4,459
Preferred units distributions	(2,176)	(1,903)	(6,485)	(5,352)
Net (loss) income attributable to SL Green	(9,541)	(20,229)	8,915	(412,679)
Perpetual preferred stock dividends	(3,738)	(3,738)	(11,213)	(11,213)
Net loss attributable to SL Green common stockholders	$ (13,279)	$ (23,967)	$ (2,298)	$ (423,892)
Basic loss per share (in dollars per share)	$ (0.21)	$ (0.38)	$ (0.06)	$ (6.63)
Diluted loss per share (in dollars per share)	$ (0.21)	$ (0.38)	$ (0.06)	$ (6.63)
Basic weighted average common shares outstanding (in shares)	64,388	64,114	64,355	64,099
Diluted weighted average common shares and common share equivalents outstanding (in shares)	64,388	68,296	64,355	68,274

Corporate Indebtedness (Tables)

9 Months Ended

Sep. 30, 2024

Debt Disclosure [Abstract]

Schedule of Senior Unsecured Notes and Other Related Disclosures by Scheduled Maturity Date

The following table sets forth our senior unsecured notes and other related disclosures as of September 30, 2024 and December 31, 2023, respectively, by scheduled maturity date (dollars in thousands):


Issuance	September 30, 2024 Unpaid Principal Balance		September 30, 2024 Accreted Balance		December 31, 2023 Accreted Balance		Interest Rate (1)			Initial Term (in Years)	Maturity Date
December 17, 2015 (2)	$	100,000	$	100,000	$	100,000		4.27	%	10	December 2025


	$	100,000	$	100,000	$	100,000
Deferred financing costs, net	—		(128)		(205)
	$	100,000	$	99,872	$	99,795

(1)Interest rate as of September 30, 2024.

(2)Issued by the Company and the Operating Partnership as co-obligors in a private placement.

Schedule of Combined Aggregate Principal Maturities

Combined aggregate principal maturities of mortgages and other loans payable, the 2021 credit facility, trust preferred securities, senior unsecured notes and our share of joint venture debt as of September 30, 2024, including as-of-right extension options but excluding other extension options, were as follows (in thousands):


	Scheduled Amortization		Principal		Revolving Credit Facility		Unsecured Term Loans		Trust Preferred Securities		Senior Unsecured Notes		Total		Joint Venture Debt
Remaining 2024	$	—	$	272,750	$	—	$	200,000	$	—	$	—	$	472,750	$	473,597
2025	—		430,900		—		—		—		100,000		530,900		1,910,561
2026	—		190,148		—		—		—		—		190,148		923,620
2027	—		550,000		735,000		1,050,000		—		—		2,335,000		1,438,338
2028	—		205,000		—		—		—		—		205,000		—
Thereafter	—		—		—		—		100,000		—		100,000		2,130,300
	$	—	$	1,648,798	$	735,000	$	1,250,000	$	100,000	$	100,000	$	3,833,798	$	6,876,416

Schedule of Consolidated Interest Expense, Excluding Capitalized Interest

Consolidated interest expense, excluding capitalized interest, was comprised of the following (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Interest expense before capitalized interest	$	51,342	$	52,877	$	149,713	$	183,652
Interest on financing leases	1,127		1,113		3,371		3,329
Capitalized interest	(9,492)		(25,483)		(41,226)		(77,916)
Amortization of discount on assumed debt	167		—		331		2,842
Interest income	(1,053)		(1,067)		(3,122)		(2,193)
Interest expense, net	$	42,091	$	27,440	$	109,067	$	109,714

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69E

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-8

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-6

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-7

+ Details

Accumulated Other Comprehensive Income

9 Months Ended

Sep. 30, 2024

Equity [Abstract]

Accumulated Other Comprehensive Income

Stockholders’ Equity of the Company

Common Stock

Share Repurchase Program

Our Board of Directors has approved a $3.5 billion share repurchase program under which we can buy shares of our common stock.

Perpetual Preferred Stock

Dividend Reinvestment and Stock Purchase Plan ("DRSPP")


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Shares of common stock issued	338,704		2,695		341,180		14,736
Dividend reinvestments/stock purchases under the DRSPP	$	23,633	$	97	$	23,754	$	439

Earnings per Share

SL Green's earnings per share for the three and nine months ended September 30, 2024 and 2023 are computed as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Numerator	2024		2023		2024		2023
Basic Earnings:
Loss attributable to SL Green common stockholders	$	(13,279)	$	(23,967)	$	(2,298)	$	(423,892)
Less: distributed earnings allocated to participating securities	(435)		(408)		(1,309)		(1,225)

Net loss attributable to SL Green common stockholders (numerator for basic earnings per share)	$	(13,714)	$	(24,375)	$	(3,607)	$	(425,117)
Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares	—		—		—		—

Add back: effect of dilutive securities (redemption of units to common shares)	—		(1,574)		—		(27,493)
Net loss attributable to SL Green common stockholders (numerator for diluted earnings per share)	$	(13,714)	$	(25,949)	$	(3,607)	$	(452,610)


	Three Months Ended September 30,		Nine Months Ended September 30,
Denominator	2024	2023	2024	2023
Basic Shares:
Weighted average common stock outstanding	64,388	64,114	64,355	64,099
Effect of Dilutive Securities:
Operating Partnership units redeemable for common shares	—	4,182	—	4,175


Diluted weighted average common stock outstanding	64,388	68,296	64,355	68,274

Partners' Capital of the Operating Partnership

Net income (loss) allocated to the preferred unitholders and common unitholders reflects their pro rata share of net income (loss) and distributions.

Limited Partner Units

As of September 30, 2024, limited partners, other than SL Green, owned 6.42%, or 4,474,406 common units, of the Operating Partnership.

Preferred Units

Earnings per Unit

The Operating Partnership's earnings per unit for the three and nine months ended September 30, 2024 and 2023, respectively, are computed as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Numerator	2024		2023		2024		2023
Basic Earnings:
Net loss attributable to SLGOP common unitholders	$	(14,193)	$	(25,541)	$	(2,464)	$	(451,385)
Less: distributed earnings allocated to participating securities	(1,147)		(408)		(3,415)		(1,225)

Net loss attributable to SLGOP common unitholders (numerator for basic earnings per unit)	$	(15,340)	$	(25,949)	$	(5,879)	$	(452,610)


Net loss attributable to SLGOP common unitholders (numerator for diluted earnings per unit)	$	(15,340)	$	(25,949)	$	(5,879)	$	(452,610)


	Three Months Ended September 30,		Nine Months Ended September 30,
Denominator	2024	2023	2024	2023
Basic units:
Weighted average common units outstanding	67,999	68,296	68,092	68,274



Diluted weighted average common units outstanding	67,999	68,296	68,092	68,274

Accumulated Other Comprehensive Income

The following tables set forth the changes in accumulated other comprehensive income by component as of September 30, 2024 (in thousands):


	Net unrealized gain (loss) on derivative instruments (1)		SL Green’s share of joint venture net unrealized loss on derivative instruments (2)		Net unrealized (loss) gain on marketable securities		Total
Balance at December 31, 2023	$	25,352	$	(6,084)	$	(1,791)	$	17,477
Other comprehensive (loss) income before reclassifications	3,864		(11,035)		1,103		(6,068)
Amounts reclassified from accumulated other comprehensive (loss) income	(27,921)		(10,796)		—		(38,717)
Balance at September 30, 2024	$	1,295	$	(27,915)	$	(688)	$	(27,308)

- Definition

The entire disclosure for equity.

+ References

+ Details

Significant Accounting Policies - Investment in Marketable Securities - Additional Information (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024 USD ($) security	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) security	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Real Estate [Line Items]
Proceeds from sale of marketable securities	$ 0	$ 0	$ 0	$ 0
Equity marketable securities	0		0		$ 0
Commercial mortgage-backed securities
Real Estate [Line Items]
Cost basis of commercial mortgage backed securities	$ 16,900,000		$ 16,900,000		11,500,000
Number of securities in unrealized gain position \| security	1		1
Unrealized gain			$ 100,000
Fair market value	$ 5,400,000		5,400,000
Unrealized loss			900,000		1,900,000
Fair value of security in a continuous unrealized loss position for less than 12 months	$ 11,100,000		$ 11,100,000		$ 9,600,000
Debt securities, available-for-sale, continuous unrealized loss position, less than 12 months, number of positions \| security	2		2
Debt securities, available-for-sale, continuous unrealized loss position, 12 months or longer, number of positions \| security	1		1

Fair Value Measurements (Details) - USD ($) $ in Thousands	1 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2021
Fair Value of Financial Instruments
Marketable securities available-for-sale		$ 16,522	$ 9,591
Interest rate cap and swap agreements (included in Other assets)		17,026	33,456
Real estate loans held by consolidated securitization vehicles		586,823	0
Interest rate cap and swap agreements (included in Other liabilities)		29,372	17,108
Senior obligations of consolidated securitization vehicles		571,711	0
Secured borrowings		237,454	0
Debt and preferred equity investments		293,924	346,745
Carrying Value		293,924	346,745
10 East 53rd Street
Fair Value of Financial Instruments
Ownership Interest Sold	45.00%
Investment fair value adjustment	$ 55,700
National Pension Service of Korea / Hines Interest LP / International Investor \| One Madison Avenue
Fair Value of Financial Instruments
Investment in joint venture aggregate maximum ownership percentage				25.00%
Variable Rate Debt
Fair Value of Financial Instruments
Estimated fair value of debt and preferred equity investments, low end of range		60,900
Estimated fair value of debt and preferred equity investments, high end of range		60,100
Carrying Value
Fair Value of Financial Instruments
Debt and preferred equity investments		293,924	346,745
Fixed rate debt		3,287,898	3,237,386
Variable rate debt		545,900	270,000
Total		3,833,798	3,507,386
Carrying Value		293,924	346,745
Fair Value
Fair Value of Financial Instruments
Total		3,797,656	3,453,125
Estimated fair value of debt and preferred equity investments, low end of range		300,000	300,000
Level 1
Fair Value of Financial Instruments
Marketable securities available-for-sale		0	0
Interest rate cap and swap agreements (included in Other assets)		0	0
Real estate loans held by consolidated securitization vehicles		0
Interest rate cap and swap agreements (included in Other liabilities)		0	0
Senior obligations of consolidated securitization vehicles		0
Secured borrowings		0
Level 2
Fair Value of Financial Instruments
Marketable securities available-for-sale		16,522	9,591
Interest rate cap and swap agreements (included in Other assets)		17,026	33,456
Real estate loans held by consolidated securitization vehicles		586,823
Interest rate cap and swap agreements (included in Other liabilities)		29,372	17,108
Senior obligations of consolidated securitization vehicles		571,711
Secured borrowings		0
Level 3
Fair Value of Financial Instruments
Marketable securities available-for-sale		0	0
Interest rate cap and swap agreements (included in Other assets)		0	0
Real estate loans held by consolidated securitization vehicles		0
Interest rate cap and swap agreements (included in Other liabilities)		0	0
Senior obligations of consolidated securitization vehicles		0
Secured borrowings		237,454
Level 3 \| Fair Value
Fair Value of Financial Instruments
Fixed rate debt		3,252,374	3,184,338
Variable rate debt		$ 545,282	$ 268,787

Segment Information

9 Months Ended

Sep. 30, 2024

Segment Reporting [Abstract]

Segment Information

The Company has three reportable segments, real estate, debt and preferred equity investments, and SUMMIT. In the fourth quarter of 2023, due to quantitative thresholds, SUMMIT was identified as a reportable segment. As such, prior period segment data has been restated to reflect SUMMIT as a reportable segment for comparative purposes.

We evaluate real estate performance and allocate resources based on earnings contributions.

The primary sources of revenue are generated from tenant rents, escalations and reimbursement revenue. Real estate property operating expenses consist primarily of security, maintenance, utility costs, insurance, real estate taxes and, at certain properties, ground rent expense. See Note 5, "Debt and Preferred Equity Investments," for additional details on our debt and preferred equity investments. SUMMIT currently operates one location at One Vanderbilt Avenue in midtown Manhattan with the primary source of revenue generated from ticket sales.

Selected consolidated results of operations for the three and nine months ended September 30, 2024 and 2023, and selected asset information as of September 30, 2024 and December 31, 2023, regarding our operating segments are as follows (in thousands):


	Real Estate Segment		SUMMIT Segment		Debt and Preferred Equity Segment		Total Company
Total revenues
Three months ended:
September 30, 2024	$	183,139	$	36,437	$	10,115	$	229,691
September 30, 2023	$	165,428	$	35,069	$	9,689	$	210,186
Nine months ended:
September 30, 2024	$	522,041	$	94,643	$	23,709	$	640,393
September 30, 2023	$	591,117	$	83,020	$	27,849	$	701,986
Net income (loss)
Three months ended:
September 30, 2024	$	(18,326)	$	(362)	$	9,424	$	(9,264)
September 30, 2023	$	(20,385)	$	(1,897)	$	588	$	(21,694)
Nine months ended:
September 30, 2024	$	(11,745)	$	11,202	$	11,627	$	11,084
September 30, 2023	$	(444,904)	$	(1,101)	$	6,726	$	(439,279)
Total assets
As of:
September 30, 2024	$	8,707,930	$	478,288	$	1,029,854	$	10,216,072
December 31, 2023	$	8,707,147	$	464,799	$	359,235	$	9,531,181

We allocate loan loss reserves, net of recoveries, and transaction related costs to the debt and preferred equity segment. We do not allocate marketing, general and administrative expenses to the debt and preferred equity segment because that segment does not have dedicated personnel and the use of personnel and resources is dependent on transaction volume between the three segments, which varies between periods. In addition, we base performance on the individual segments prior to allocating marketing, general and administrative expenses. SUMMIT segment incurs its own marketing, general and administrative expenses for its dedicated personnel, which are included in SUMMIT Operator expenses in the consolidated statement of operations. For the three and nine months ended September 30, 2024, marketing, general and administrative expenses totaled $21.0 million and $62.4 million, respectively. For the three and nine months ended September 30, 2023, marketing, general and administrative expenses totaled $22.9 million and $69.1 million, respectively. All other expenses, except interest and SUMMIT operator expenses, relate entirely to the real estate assets.

There were no transactions between the above three segments other than the SUMMIT lease with our One Vanderbilt Avenue joint venture, which is part of the real estate segment. See Note 10, "Related Party Transactions."

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details

Stockholders' Equity of the Company - Additional Information (Details) - $ / shares	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Equity, Class of Treasury Stock [Line Items]
Authorized capital stock (shares)	260,000,000
Authorized shares, par value (in dollars per share)	$ 0.01
Common stock, shares authorized (in shares)	160,000,000		160,000,000
Common stock, par value (in dollars per share)	$ 0.01		$ 0.01
Excess stock, shares authorized (shares)	75,000,000
Excess stock, par value (in dollars per share)	$ 0.01
Preferred stock, shares authorized (shares)	25,000,000
Preferred stock, par value (in dollars per share)	$ 0.01
Excess shares issued (shares)	0
Excess shares outstanding (in shares)	0
Common Stock
Equity, Class of Treasury Stock [Line Items]
Shares, outstanding (in shares)	65,235,000	64,814,000	64,726,000	64,398,000	64,387,000	64,380,000
SL Green Operating Partnership \| Common Stock
Equity, Class of Treasury Stock [Line Items]
Shares, outstanding (in shares)	65,235,013
Shares, issued (in shares)	65,235,013

Financial Instruments: Derivatives and Hedging - Schedule of Effect of Derivative Financial Instruments on Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Financial Instruments: Derivatives and Hedging
Amount of Gain Recognized in Other Comprehensive (Loss) Income	$ (57,698)	$ 28,837	$ (7,808)	$ 66,091
Amount of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income	14,470	16,038	41,244	43,029
Joint venture
Financial Instruments: Derivatives and Hedging
Amount of Gain Recognized in Other Comprehensive (Loss) Income	(19,493)	3,927	(11,951)	13,467
Amount of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income	4,222	4,616	11,498	11,986
Interest Rate Contract
Financial Instruments: Derivatives and Hedging
Amount of Gain Recognized in Other Comprehensive (Loss) Income	(38,205)	24,910	4,143	52,624
Amount of Gain Reclassified from Accumulated Other Comprehensive (Loss) Income into Income	$ 10,248	$ 11,422	$ 29,746	$ 31,043

Debt and Preferred Equity Investments - Schedule of Activity in Debt and Preferred Equity Investments (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024 USD ($) investment	Dec. 31, 2023 USD ($) investment
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance at beginning of period	$ 346,745	$ 623,280
Redemptions/sales/syndications/equity ownership/amortization	(64,629)	(349,947)
Net change in loan loss reserves	0	(6,890)
Balance at end of period	$ 293,924	$ 346,745
Number of investments, nonperforming \| investment	2	2
Carrying Value	$ 293,924	$ 346,745
Preferred Equity (4)
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Carrying Value	134,474
Preferred Equity (4) \| 625 Madison Avenue
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Carrying Value	209,900
Total floating rate
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Carrying Value	109,604	168,899
Alternative Strategy Portfolio (3) \| Total floating rate
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Carrying Value	49,800
Debt Investment
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Originations/Accretion	5,334	72,160
Preferred Equity Investments
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Originations/Accretion	$ 6,474	$ 8,142

Financial Instruments: Derivatives and Hedging - Schedule of Notional and Fair Value of Derivative Financial Instruments and Foreign Currency Hedges (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financial Instruments: Derivatives and Hedging
Fair Value	$ 17,026	$ 33,456
Interest Rate Contract
Financial Instruments: Derivatives and Hedging
Fair Value	(12,346)
Interest Rate Contract \| Joint venture
Financial Instruments: Derivatives and Hedging
Fair Value	(26,909)
Interest Rate Cap Expiring in February 2025
Financial Instruments: Derivatives and Hedging
Notional Value	$ 205,000
Strike Rate	4.00%
Fair Value	$ 395
Interest Rate Cap Expiring in June 2025
Financial Instruments: Derivatives and Hedging
Notional Value	$ 370,000
Strike Rate	3.25%
Fair Value	$ 2,287
Interest Rate Cap Expiring in June 2025
Financial Instruments: Derivatives and Hedging
Notional Value	$ 370,000
Strike Rate	3.25%
Fair Value	$ (2,275)
Interest Rate Cap Expiring in June 2025
Financial Instruments: Derivatives and Hedging
Notional Value	$ 68,678
Strike Rate	4.00%
Fair Value	$ (161)
Interest Rate Swap Expiring January 2026
Financial Instruments: Derivatives and Hedging
Notional Value	$ 150,000
Strike Rate	2.621%
Fair Value	$ 1,870
Interest Rate Swap Expiring January 2026, 2
Financial Instruments: Derivatives and Hedging
Notional Value	$ 200,000
Strike Rate	2.662%
Fair Value	$ 2,393
Interest Rate Swap Expiring December 2026
Financial Instruments: Derivatives and Hedging
Notional Value	$ 125,000
Strike Rate	3.667%
Fair Value	$ (826)
Interest Rate Swap Expiring December 2026, 2
Financial Instruments: Derivatives and Hedging
Notional Value	$ 125,000
Strike Rate	3.67%
Fair Value	$ (841)
Interest Rate Swap Expiring in February 2027
Financial Instruments: Derivatives and Hedging
Notional Value	$ 100,000
Strike Rate	2.903%
Fair Value	$ 991
Interest Rate Swap Expiring in February 2027, 2
Financial Instruments: Derivatives and Hedging
Notional Value	$ 100,000
Strike Rate	2.733%
Fair Value	$ 1,374
Interest Rate Swap Expiring in February 2027, 3
Financial Instruments: Derivatives and Hedging
Notional Value	$ 50,000
Strike Rate	2.463%
Fair Value	$ 992
Interest Rate Swap Expiring in February 2027, 4
Financial Instruments: Derivatives and Hedging
Notional Value	$ 200,000
Strike Rate	2.591%
Fair Value	$ 3,391
Interest Rate Swap Expiring in May 2027
Financial Instruments: Derivatives and Hedging
Notional Value	$ 300,000
Strike Rate	2.866%
Fair Value	$ 3,333
Interest Rate Swap Expiring in May 2027, 2
Financial Instruments: Derivatives and Hedging
Notional Value	$ 150,000
Strike Rate	3.524%
Fair Value	$ (792)
Interest Rate Swap Expiring in June 2027
Financial Instruments: Derivatives and Hedging
Notional Value	$ 370,000
Strike Rate	3.888%
Fair Value	$ (5,513)
Interest Rate Swap Expiring in June 2027 2
Financial Instruments: Derivatives and Hedging
Notional Value	$ 68,678
Strike Rate	4.466%
Fair Value	$ (2,076)
Interest Rate Swap Expiring in November 2027
Financial Instruments: Derivatives and Hedging
Notional Value	$ 300,000
Strike Rate	4.487%
Fair Value	$ (10,723)
Interest Rate Swap Expiring in January 2028
Financial Instruments: Derivatives and Hedging
Notional Value	$ 100,000
Strike Rate	3.756%
Fair Value	$ (1,482)
Interest Rate Swap Expiring in May 2028
Financial Instruments: Derivatives and Hedging
Notional Value	$ 204,963
Strike Rate	3.915%
Fair Value	$ (4,683)
Interest Rate Cap Expiring November 2024 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 312,783
Strike Rate	4.00%
Fair Value	$ 294
Interest Rate Cap Expiring November 2024, 2 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 312,783
Strike Rate	4.00%
Fair Value	$ 294
Interest Rate Cap Expiring in July 2025, 2 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 285,000
Strike Rate	4.00%
Fair Value	$ 671
Interest Rate Swap Expiring February 2026 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 250,000
Strike Rate	3.608%
Fair Value	$ (67)
Interest Rate Swap Expiring February 2026, 2 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 250,000
Strike Rate	3.608%
Fair Value	$ (67)
Interest Rate Swap Expiring February 2026, 3 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 177,000
Strike Rate	1.555%
Fair Value	$ 4,836
Interest Rate Cap Expiring November 2024, 2 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 268,750
Strike Rate	4.039%
Fair Value	$ (7,984)
Interest Rate Swap Expiring September 2028, 2 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 268,750
Strike Rate	4.058%
Fair Value	$ (8,176)
Interest Rate Cap Expiring September 2028, 3 \| Joint venture
Financial Instruments: Derivatives and Hedging
Notional Value	$ 537,500
Strike Rate	4.065%
Fair Value	$ (16,710)

Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward]
Beginning balance	$ 3,855,925
Ending balance	3,620,005
Deferred net losses from terminated hedges	(300)	$ (400)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward]
Beginning balance	17,477
Other comprehensive (loss) income before reclassifications	(6,068)
Amounts reclassified from accumulated other comprehensive (loss) income	(38,717)
Ending balance	(27,308)
Net unrealized gain (loss) on derivative instruments
Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward]
Beginning balance	25,352
Other comprehensive (loss) income before reclassifications	3,864
Amounts reclassified from accumulated other comprehensive (loss) income	(27,921)
Ending balance	1,295
Net unrealized (loss) gain on marketable securities
Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward]
Beginning balance	(1,791)
Other comprehensive (loss) income before reclassifications	1,103
Amounts reclassified from accumulated other comprehensive (loss) income	0
Ending balance	(688)
Joint venture
Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward]
Beginning balance	5,036,237
Ending balance	5,307,010
Joint venture \| Net unrealized gain (loss) on derivative instruments
Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward]
Beginning balance	(6,084)
Other comprehensive (loss) income before reclassifications	(11,035)
Amounts reclassified from accumulated other comprehensive (loss) income	(10,796)
Ending balance	$ (27,915)

- Definition

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References + Details

- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

+ References + Details

- Definition

Amount of equity (deficit) attributable to parent and noncontrolling interest. Excludes temporary equity.

+ References

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+ Details

Debt and Preferred Equity Investments - Schedule of Carrying Value of Debt and Preferred Equity Investment Portfolio by Year of Origination and Risk Rating (Details) $ in Thousands	Sep. 30, 2024 USD ($) investment	Dec. 31, 2023 USD ($) investment
Financing Receivable, Credit Quality Indicator [Line Items]
2024	$ 0
2023	0
2022	0
Prior	293,924
Carrying value	$ 293,924	$ 346,745
Number of investments, nonperforming \| investment	2	2
Carrying Value	$ 293,924	$ 346,745
Total floating rate
Financing Receivable, Credit Quality Indicator [Line Items]
Carrying Value	109,604	168,899
Alternative Strategy Portfolio (3) \| Total floating rate
Financing Receivable, Credit Quality Indicator [Line Items]
Carrying Value	49,800
1 - Low Risk Assets - Low probability of loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
Prior	154,474
Carrying value	154,474	210,333
2 - Watch List Assets - Higher potential for loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
Prior	139,450
Carrying value	139,450	136,412
3 - High Risk Assets - Loss more likely than not
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
Prior	0
Carrying value	$ 0	$ 0

Stockholders' Equity of the Company (Tables)

9 Months Ended

Sep. 30, 2024

Stockholders' Equity Note [Abstract]

Schedule of Common Stock Issued and Proceeds Received Dividend Reinvestments


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Shares of common stock issued	338,704		2,695		341,180		14,736
Dividend reinvestments/stock purchases under the DRSPP	$	23,633	$	97	$	23,754	$	439

Schedule of Earnings Per Share

SL Green's earnings per share for the three and nine months ended September 30, 2024 and 2023 are computed as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Numerator	2024		2023		2024		2023
Basic Earnings:
Loss attributable to SL Green common stockholders	$	(13,279)	$	(23,967)	$	(2,298)	$	(423,892)
Less: distributed earnings allocated to participating securities	(435)		(408)		(1,309)		(1,225)

Net loss attributable to SL Green common stockholders (numerator for basic earnings per share)	$	(13,714)	$	(24,375)	$	(3,607)	$	(425,117)
Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares	—		—		—		—

Add back: effect of dilutive securities (redemption of units to common shares)	—		(1,574)		—		(27,493)
Net loss attributable to SL Green common stockholders (numerator for diluted earnings per share)	$	(13,714)	$	(25,949)	$	(3,607)	$	(452,610)


	Three Months Ended September 30,		Nine Months Ended September 30,
Denominator	2024	2023	2024	2023
Basic Shares:
Weighted average common stock outstanding	64,388	64,114	64,355	64,099
Effect of Dilutive Securities:
Operating Partnership units redeemable for common shares	—	4,182	—	4,175


Diluted weighted average common stock outstanding	64,388	68,296	64,355	68,274

Cover Page - shares	9 Months Ended
Cover Page - shares	Sep. 30, 2024	Oct. 30, 2024
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2024
Document Transition Report	false
Entity File Number	1-13199
Entity Registrant Name	SL GREEN REALTY CORP
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	13-3956775
Entity Address, Address Line One	One Vanderbilt Avenue
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10017
City Area Code	212
Local Phone Number	594-2700
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		65,618,742
Entity Central Index Key	0001040971
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common Stock
Document Information [Line Items]
Trading Symbol	SLG
Title of 12(b) Security	Common Stock, $0.01 par value
Security Exchange Name	NYSE
Preferred stock
Document Information [Line Items]
Trading Symbol	SLG.PRI
Title of 12(b) Security	6.500% Series I Cumulative Redeemable Preferred Stock, $0.01 par value
Security Exchange Name	NYSE
SL Green Operating Partnership
Document Information [Line Items]
Entity File Number	33-167793-02
Entity Registrant Name	SL GREEN OPERATING PARTNERSHIP, L.P.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-3960938
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		306,064
Entity Central Index Key	0001492869
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Amendment Flag	false

Financial Instruments: Derivatives and Hedging - Narratives (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Financial Instruments: Derivatives and Hedging
Fair value of derivatives in a net liability position	$ (29.7)		$ (29.7)
Aggregate termination value	31.0		31.0
Estimated current balance held in accumulated other comprehensive loss to be reclassified into earnings within the next 12 months			(11.2)
Interest Expense
Financial Instruments: Derivatives and Hedging
Gain (loss) from changes in fair value	0.2	$ 0.0	0.1	$ 0.2
Income Loss From Equity Method Investments
Financial Instruments: Derivatives and Hedging
Estimated current balance held in accumulated other comprehensive loss to be reclassified into earnings within the next 12 months			1.3
Interest Rate Cap
Financial Instruments: Derivatives and Hedging
Gain (loss) from changes in fair value	$ 9.2	$ 0.0	$ 2.8	$ 0.2

Stockholders' Equity of the Company - Stock Repurchase Program (Details) $ in Billions	3 Months Ended	9 Months Ended
	Sep. 30, 2024 USD ($) shares	Sep. 30, 2024 USD ($) shares
Stockholders' Equity Note [Abstract]
Stock repurchase program, authorized amount \| $	$ 3.5	$ 3.5
Share repurchased (in shares) \| shares	36,107,719	0

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References + Details

Property Acquisitions and Consolidations

9 Months Ended

Sep. 30, 2024

Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]

Property Acquisitions and Consolidations

Property Acquisitions

During the nine months ended September 30, 2024, we did not acquire any properties from a third party.

Property Consolidations

The following table summarizes the properties consolidated during the nine months ended September 30, 2024:

Property

Consolidation Date

Property Type

Approximate Square Feet

Gross Asset Valuation
(in millions)

10 East 53rd Street (1)

March 2024

Fee Interest

354,300

236.0

Debt and Preferred Equity Investments - Schedule of Debt and Preferred Equity Investments (Details) $ in Thousands	Sep. 30, 2024 USD ($) investment	Dec. 31, 2023 USD ($) investment
Debt Instrument [Line Items]
Carrying Value	$ 293,924	$ 346,745
Senior Financing	$ 1,054,021
Number of investments, nonperforming \| investment	2	2
Total floating rate
Debt Instrument [Line Items]
Carrying Value	$ 109,450
Face Value	109,604
Total fixed rate
Debt Instrument [Line Items]
Carrying Value	184,474
Face Value	184,474
Mezzanine Debt
Debt Instrument [Line Items]
Carrying Value	159,450
Senior Financing	804,021
Mezzanine Debt \| Total floating rate
Debt Instrument [Line Items]
Carrying Value	109,450
Face Value	109,604
Mezzanine Debt \| Total fixed rate
Debt Instrument [Line Items]
Carrying Value	50,000
Face Value	50,000
Preferred Equity (4)
Debt Instrument [Line Items]
Carrying Value	134,474
Senior Financing	250,000
Preferred Equity (4) \| 625 Madison Avenue
Debt Instrument [Line Items]
Carrying Value	209,900
Preferred Equity (4) \| Total floating rate
Debt Instrument [Line Items]
Carrying Value	0
Face Value	$ 0
Basis spread on variable rate	0.00%
Preferred Equity (4) \| Total fixed rate
Debt Instrument [Line Items]
Carrying Value	$ 134,474
Face Value	$ 134,474
Interest Rate	6.50%
Minimum \| Mezzanine Debt \| Total floating rate
Debt Instrument [Line Items]
Basis spread on variable rate	5.00%
Minimum \| Mezzanine Debt \| Total fixed rate
Debt Instrument [Line Items]
Interest Rate	8.00%
Maximum \| Mezzanine Debt \| Total floating rate
Debt Instrument [Line Items]
Basis spread on variable rate	12.11%
Maximum \| Mezzanine Debt \| Total fixed rate
Debt Instrument [Line Items]
Interest Rate	8.40%

Consolidated Statements of Capital (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Cash distributions declared (per common unit, none of which represented a return of capital for federal income tax purposes) (in dollars per share)	$ 0.750	$ 0.812	$ 2.250	$ 2.437
SL Green Operating Partnership
Cash distributions declared (per common unit, none of which represented a return of capital for federal income tax purposes) (in dollars per share)	$ 0.750	$ 0.812	$ 2.250	$ 2.437

Investments in Unconsolidated Joint Ventures

9 Months Ended

Sep. 30, 2024

Equity Method Investments and Joint Ventures [Abstract]

Investments in Unconsolidated Joint Ventures

We have investments in several real estate joint ventures with various partners. As of September 30, 2024, the book value of these investments was $2.9 billion, net of investments with negative book values totaling $179.1 million for which we have an implicit commitment to fund future capital needs.

As of September 30, 2024, 800 Third Avenue and our preferred equity investment in 625 Madison Avenue are VIEs in which we are not the primary beneficiary. As of December 31, 2023, 800 Third Avenue and 625 Madison Avenue were VIEs in which we are not the primary beneficiary. Our net equity investment in these VIEs was $261.0 million and $437.9 million as of September 30, 2024 and December 31, 2023, respectively. Our maximum loss is limited to the amount of our equity investment in these VIEs. See the "Principles of Consolidation" section of Note 2, "Significant Accounting Policies." All other investments below are voting interest entities. As we do not control, but have significant influence over the joint ventures listed below, we account for them under the equity method of accounting.

The table below provides general information on each of our joint ventures as of September 30, 2024:


Property	Partner	Ownership Interest (1)	Economic Interest (1)	Unaudited Approximate Square Feet
100 Park Avenue	Prudential Real Estate Investors	49.90%	49.90%	834,000
800 Third Avenue	Private Investors	60.52%	60.52%	526,000
919 Third Avenue	New York State Teacher's Retirement System	51.00%	51.00%	1,454,000
11 West 34th Street (2)	Private Investor / Wharton Properties	30.00%	30.00%	17,150
280 Park Avenue	Vornado Realty Trust	50.00%	50.00%	1,219,158
1552-1560 Broadway (2) (3)	Wharton Properties	50.00%	50.00%	57,718
650 Fifth Avenue (2) (4)	Wharton Properties	50.00%	50.00%	69,214
11 Madison Avenue	PGIM Real Estate	60.00%	60.00%	2,314,000
One Vanderbilt Avenue	National Pension Service of Korea / Hines Interest LP	71.01%	71.01%	1,657,198
Worldwide Plaza (2)	RXR Realty / New York REIT	24.95%	24.95%	2,048,725
1515 Broadway	Allianz Real Estate of America	56.87%	56.87%	1,750,000
2 Herald Square (2) (5)	Israeli Institutional Investor	95.00%	95.00%	369,000
115 Spring Street (2)	Private Investor	51.00%	51.00%	5,218
15 Beekman (6)	A fund managed by Meritz Alternative Investment Management	20.00%	20.00%	221,884
85 Fifth Avenue	Wells Fargo	36.27%	36.27%	12,946
One Madison Avenue (7)	National Pension Service of Korea / Hines Interest LP / International Investor	25.50%	25.50%	1,048,700
220 East 42nd Street	A fund managed by Meritz Alternative Investment Management	51.00%	51.00%	1,135,000
450 Park Avenue (8)	Korean Institutional Investor / Israeli Institutional Investor	50.10%	25.10%	337,000
5 Times Square (2)	RXR Realty led investment group	31.55%	31.55%	1,131,735
245 Park Avenue	U.S. Affiliate of Mori Trust Co., Ltd	50.10%	50.10%	1,782,793
625 Madison Avenue (9)	Private Investor	90.93%	90.93%	591,123

(2)Included in the Company's alternative strategy portfolio.

(3)The joint venture owns a long-term leasehold interest in the retail space and certain other spaces at 1560 Broadway, which is adjacent to 1552 Broadway.

(4)The joint venture owns a long-term leasehold interest in the retail space at 650 Fifth Avenue.

(6)In 2020, the Company formed a joint venture, which then entered into a long-term sublease with the Company.

Disposition of Joint Venture Interests or Properties

The following table summarizes the investments in unconsolidated joint ventures sold during the nine months ended September 30, 2024:


Property	Ownership Interest Sold	Disposition Date	Gross Asset Valuation (in millions)		Gain (Loss) on Sale (in millions) (1) (2)
717 Fifth Avenue	10.92%	January 2024	$	963.0	$	24.9
625 Madison Avenue (3)	90.43%	May 2024	634.6		(7.6)

(1)Represents the Company's share of the gain.

Joint Venture Mortgages and Other Loans Payable

We generally finance our joint ventures with non-recourse debt. In certain cases, we may provide guarantees or master leases, which terminate upon the satisfaction of specified circumstances or repayment of the underlying loans. The mortgage notes and other loans payable collateralized by the respective joint venture properties and assignment of leases as of September 30, 2024 and December 31, 2023, respectively, are as follows (dollars in thousands):


							Principal Outstanding				Principal Outstanding
	Economic		Current Maturity	Final Maturity	Interest		September 30, 2024				December 31, 2023
Property	Interest (1)		Date	Date (2)	Rate (3)		Gross		SLG Share		Gross		SLG Share
Fixed Rate Debt:
650 Fifth Avenue (4)	50.00	%	February 2025	July 2025		5.45%	$	65,000	$	32,500	$	65,000	$	32,500
1515 Broadway	56.87	%	March 2025	March 2025		3.93%	746,330		424,431		762,002		433,344
115 Spring Street (4)	51.00	%	March 2025	March 2025		5.50%	65,550		33,431		65,550		33,431
450 Park Avenue	25.10	%	June 2025	June 2027		6.10%	282,789		70,980		271,394		68,120
11 Madison Avenue	60.00	%	September 2025	September 2025		3.84%	1,400,000		840,000		1,400,000		840,000
One Madison Avenue (5)	25.50	%	November 2025	November 2026		7.10%	625,567		159,520		733,103		186,941
15 Beekman	20.00	%	January 2026	January 2028		5.99%	120,000		24,000		—		—
800 Third Avenue	60.52	%	February 2026	February 2026		3.37%	177,000		107,120		177,000		107,120
919 Third Avenue	51.00	%	April 2026	April 2028		6.11%	500,000		255,000		500,000		255,000
280 Park Avenue	50.00	%	September 2026	September 2028		5.84%	1,075,000		537,500		—		—
245 Park Avenue	50.10	%	June 2027	June 2027		4.30%	1,768,000		885,768		1,768,000		885,768
Worldwide Plaza (4)	24.95	%	November 2027	November 2027		3.98%	1,200,000		299,400		1,200,000		299,400
220 East 42nd Street	51.00	%	December 2027	December 2027		6.77%	496,412		253,170		505,412		257,760
One Vanderbilt Avenue	71.01	%	July 2031	July 2031		2.95%	3,000,000		2,130,300		3,000,000		2,130,300
5 Times Square (4)							—		—		477,783		150,740
625 Madison Avenue							—		—		199,987		180,848
10 East 53rd Street							—		—		220,000		121,000
717 Fifth Avenue							—		—		655,328		71,536
Total fixed rate debt							$	11,521,648	$	6,053,120	$	12,000,559	$	6,053,808
Floating Rate Debt:
11 West 34th Street (4)	30.00	%	February 2023 (6)	February 2023 (6)	L+	1.45%	$	23,000	$	6,900	$	23,000	$	6,900
1552 Broadway (4)	50.00	%	February 2024 (7)	February 2024 (7)	S+	2.75%	193,133		96,566		193,133		96,567
650 Fifth Avenue (4)	50.00	%	February 2025	July 2025	S+	2.25%	210,000		105,000		210,000		105,000
5 Times Square (4)	31.55	%	September 2024 (8)	September 2026 (8)	S+	4.71%	1,163,451		367,069		610,010		192,458
100 Park Avenue	49.90	%	December 2024	December 2025	S+	2.36%	360,000		179,640		360,000		179,640
One Madison Avenue (5)	25.50	%	November 2025	November 2026	S+	3.10%	267,143		68,121		—		—
280 Park Avenue							—		—		1,200,000		600,000
2 Herald Square							—		—		182,500		93,075
15 Beekman							—		—		124,137		24,827
Total floating rate debt							$	2,216,727	$	823,296	$	2,902,780	$	1,298,467
Total joint venture mortgages and other loans payable							$	13,738,375	$	6,876,416	$	14,903,339	$	7,352,275
Deferred financing costs, net							(85,064)		(47,397)		(104,062)		(54,865)
Total joint venture mortgages and other loans payable, net							$	13,653,311	$	6,829,019	$	14,799,277	$	7,297,410

(2)Reflects exercise of all available extension options. The ability to exercise extension options may be subject to certain conditions, including the operating performance of the property.

(4)Included in the Company's alternative strategy portfolio.

(6)The Company's joint venture partner is in discussions with the lender on resolution of the past maturity.

(7)The Company is in discussions with the lender on resolution of the past maturity.

(8)The joint venture has agreed to cooperate with the lender on the past due maturity.

We receive fees for providing management, leasing, construction supervision and asset management services to certain of our joint ventures. We earned $6.1 million and $12.7 million from these services, net of our ownership share of the joint ventures, for the three and nine months ended September 30, 2024, respectively. We earned $3.5 million and $16.3 million from these services, net of our ownership share of the joint ventures, for the three and nine months ended September 30, 2023, respectively. In addition, we have the ability to earn incentive fees based on the ultimate financial performance of certain of the joint venture properties.

The combined balance sheets for the unconsolidated joint ventures, at September 30, 2024 and December 31, 2023 are as follows (in thousands):


	September 30, 2024		December 31, 2023
Assets (1)
Commercial real estate property, net	$	16,534,399	$	17,561,406
Cash and restricted cash	696,010		656,038
Tenant and other receivables and deferred rents receivable	643,310		673,532
Debt and preferred equity investments, net	231,080		—
Right-of-use assets	925,461		905,934
Other assets	2,452,064		2,584,765
Total assets	$	21,482,324	$	22,381,675
Liabilities and equity (1)
Mortgages and other loans payable, net	$	13,653,311	$	14,799,277
Deferred revenue	1,011,333		1,108,180
Lease liabilities	1,011,261		990,276
Other liabilities	499,409		447,705
Equity	5,307,010		5,036,237
Total liabilities and equity	$	21,482,324	$	22,381,675
Company's investments in unconsolidated joint ventures	$	2,871,683	$	2,983,313

The combined statements of operations for the unconsolidated joint ventures, from acquisition date through the three and nine months ended September 30, 2024 and 2023, are as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Total revenues	$	376,949	$	407,148	$	1,107,295	$	1,140,889
Operating expenses	67,104		63,081		192,587		183,825
Real estate taxes	73,686		78,564		222,797		210,428
Operating lease rent	8,487		7,307		25,990		21,746
Interest expense, net of interest income	141,067		162,897		433,117		421,528
Amortization of deferred financing costs	4,487		6,897		14,718		21,140

Depreciation and amortization	137,640		138,199		407,429		380,867
Total expenses	432,471		456,945		1,296,638		1,239,534
Gain on early extinguishment of debt	—		—		233,704		—
Net (loss) income before gain (loss) on sale	$	(55,522)	$	(49,797)	$	44,361	$	(98,645)
Company's equity in net (loss) income from unconsolidated joint ventures	$	(15,428)	$	(15,126)	$	100,057	$	(44,470)

Investments in Unconsolidated Joint Ventures - Schedule of General Information on Joint Ventures (Details)	1 Months Ended	3 Months Ended			9 Months Ended
	Jan. 31, 2024 USD ($)	Sep. 30, 2024 USD ($) ft²	Mar. 31, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) ft²	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2021
General information on each joint venture
Depreciable real estate reserves and impairment \| $		$ 0		$ 389,000	$ (65,839,000)	$ (305,527,000)
Mortgages and other loans payable, net \| $		1,643,992,000			1,643,992,000		$ 1,491,319,000
625 Madison Avenue
General information on each joint venture
Depreciable real estate reserves and impairment \| $			$ 5,900,000
625 Madison Avenue \| Preferred Equity (4)
General information on each joint venture
Carrying value of investment in leasehold interest \| $		235,400,000			$ 235,400,000
Average yield (as a percent)					8.91%
Joint venture
General information on each joint venture
Mortgages and other loans payable, net \| $		$ 13,653,311,000			$ 13,653,311,000		$ 14,799,277,000
Joint venture \| 2 Herald Square
General information on each joint venture
Consideration transferred \| $	$ 0
Investment in joint venture, ownership percentage	95.00%
Prudential Real Estate Investors \| Joint venture \| 100 Park Avenue
General information on each joint venture
Ownership Interest		49.90%			49.90%
Economic Interest (as a percent)		49.90%			49.90%
Approximate Square Feet unaudited (sqft)		834,000			834,000
Private Investors \| Joint venture \| 800 Third Avenue
General information on each joint venture
Ownership Interest		60.52%			60.52%
Economic Interest (as a percent)		60.52%			60.52%
Interest rate, fixed rate debt (as a percent)		3.37%			3.37%
Approximate Square Feet unaudited (sqft)		526,000			526,000
Private Investors \| Joint venture \| 115 Spring Street
General information on each joint venture
Ownership Interest		51.00%			51.00%
Economic Interest (as a percent)		51.00%			51.00%
Interest rate, fixed rate debt (as a percent)		5.50%			5.50%
Approximate Square Feet unaudited (sqft)		5,218			5,218
Private Investors \| Joint venture \| 625 Madison Avenue
General information on each joint venture
Ownership Interest		90.93%			90.93%
Economic Interest (as a percent)		90.93%			90.93%
Approximate Square Feet unaudited (sqft)		591,123			591,123
New York State Teacher's Retirement System \| Joint venture \| 919 Third Avenue
General information on each joint venture
Ownership Interest		51.00%			51.00%
Economic Interest (as a percent)		51.00%			51.00%
Interest rate, fixed rate debt (as a percent)		6.11%			6.11%
Approximate Square Feet unaudited (sqft)		1,454,000			1,454,000
Private Investor / Wharton Properties \| Joint venture \| 11 West 34th Street
General information on each joint venture
Ownership Interest		30.00%			30.00%
Economic Interest (as a percent)		30.00%			30.00%
Approximate Square Feet unaudited (sqft)		17,150			17,150
Vornado Realty Trust \| Joint venture \| 280 Park Avenue
General information on each joint venture
Ownership Interest		50.00%			50.00%
Economic Interest (as a percent)		50.00%			50.00%
Interest rate, fixed rate debt (as a percent)		5.84%			5.84%
Approximate Square Feet unaudited (sqft)		1,219,158			1,219,158
Wharton Properties \| Joint venture \| 1552-1560 Broadway
General information on each joint venture
Ownership Interest		50.00%			50.00%
Approximate Square Feet unaudited (sqft)		57,718			57,718
Wharton Properties \| Joint venture \| 650 Fifth Avenue
General information on each joint venture
Ownership Interest		50.00%			50.00%
Economic Interest (as a percent)		50.00%			50.00%
Interest rate, fixed rate debt (as a percent)		5.45%			5.45%
Approximate Square Feet unaudited (sqft)		69,214			69,214
PGIM Real Estate \| Joint venture \| 11 Madison Avenue
General information on each joint venture
Ownership Interest		60.00%			60.00%
Economic Interest (as a percent)		60.00%			60.00%
Interest rate, fixed rate debt (as a percent)		3.84%			3.84%
Approximate Square Feet unaudited (sqft)		2,314,000			2,314,000
National Pension Service of Korea / Hines Interest LP \| Joint venture \| One Vanderbilt Avenue
General information on each joint venture
Ownership Interest		71.01%			71.01%
Economic Interest (as a percent)		71.01%			71.01%
Interest rate, fixed rate debt (as a percent)		2.95%			2.95%
Approximate Square Feet unaudited (sqft)		1,657,198			1,657,198
National Pension Service of Korea / Hines Interest LP \| Joint venture \| East 220 Street 42
General information on each joint venture
Interest rate, fixed rate debt (as a percent)		6.77%			6.77%
National Pension Service of Korea / Hines Interest LP \| Joint venture \| 5 Times Square
General information on each joint venture
Interest rate, fixed rate debt (as a percent)
RXR Realty / New York REIT \| Joint venture \| Worldwide Plaza
General information on each joint venture
Ownership Interest		24.95%			24.95%
Economic Interest (as a percent)		24.95%			24.95%
Interest rate, fixed rate debt (as a percent)		3.98%			3.98%
Approximate Square Feet unaudited (sqft)		2,048,725			2,048,725
Allianz Real Estate of America \| Joint venture \| 1515 Broadway
General information on each joint venture
Ownership Interest		56.87%			56.87%
Economic Interest (as a percent)		56.87%			56.87%
Interest rate, fixed rate debt (as a percent)		3.93%			3.93%
Approximate Square Feet unaudited (sqft)		1,750,000			1,750,000
Israeli Institutional Investor \| Joint venture \| 2 Herald Square
General information on each joint venture
Ownership Interest		95.00%			95.00%
Economic Interest (as a percent)		95.00%			95.00%
Approximate Square Feet unaudited (sqft)		369,000			369,000
A fund managed by Meritz Alternative Investment Management \| Joint venture \| 15 Beekman
General information on each joint venture
Ownership Interest		20.00%			20.00%
Economic Interest (as a percent)		20.00%			20.00%
Interest rate, fixed rate debt (as a percent)		5.99%			5.99%
Approximate Square Feet unaudited (sqft)		221,884			221,884
A fund managed by Meritz Alternative Investment Management \| Joint venture \| East 220 Street 42
General information on each joint venture
Ownership Interest		51.00%			51.00%
Economic Interest (as a percent)		51.00%			51.00%
Approximate Square Feet unaudited (sqft)		1,135,000			1,135,000
Wells Fargo \| Joint venture \| 85 Fifth Avenue
General information on each joint venture
Ownership Interest		36.27%			36.27%
Economic Interest (as a percent)		36.27%			36.27%
Approximate Square Feet unaudited (sqft)		12,946			12,946
National Pension Service of Korea / Hines Interest LP / International Investor \| One Madison Avenue
General information on each joint venture
Investment in joint venture aggregate maximum ownership percentage								25.00%
National Pension Service of Korea / Hines Interest LP / International Investor \| Joint venture \| One Madison Avenue
General information on each joint venture
Ownership Interest		25.50%			25.50%
Economic Interest (as a percent)		25.50%			25.50%
Interest rate, fixed rate debt (as a percent)		7.10%			7.10%
Approximate Square Feet unaudited (sqft)		1,048,700			1,048,700
Korean Institutional Investor / Israeli Institutional Investor \| 450 Park Avenue \| Third-Party
General information on each joint venture
Ownership Interest		49.90%			49.90%
Investment in joint venture, partners' ownership percentage		25.00%			25.00%
Korean Institutional Investor / Israeli Institutional Investor \| Joint venture \| 450 Park Avenue
General information on each joint venture
Ownership Interest		50.10%			50.10%
Economic Interest (as a percent)		25.10%			25.10%
Interest rate, fixed rate debt (as a percent)		6.10%			6.10%
Approximate Square Feet unaudited (sqft)		337,000			337,000
Investment in joint venture, ownership percentage		25.10%			25.10%
RXR Realty led investment group \| Joint venture \| 5 Times Square
General information on each joint venture
Ownership Interest		31.55%			31.55%
Economic Interest (as a percent)		31.55%			31.55%
Approximate Square Feet unaudited (sqft)		1,131,735			1,131,735
U.S. Affiliate of Mori Trust Co., Ltd \| Joint venture \| 245 Park Avenue
General information on each joint venture
Ownership Interest		50.10%			50.10%
Economic Interest (as a percent)		50.10%			50.10%
Interest rate, fixed rate debt (as a percent)		4.30%			4.30%
Approximate Square Feet unaudited (sqft)		1,782,793			1,782,793

Lease Income (Tables)

9 Months Ended

Sep. 30, 2024

Leases [Abstract]

Schedule of Operating Lease, Lease Income

The components of lease income from operating leases in our consolidated statements of operations during the three and nine months ended September 30, 2024 and 2023 were as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Fixed lease payments	$	140,450	$	131,664	$	405,130	$	457,454
Variable lease payments	17,317		19,467		45,687		60,211
Total lease payments (1)	$	157,767	$	151,131	$	450,817	$	517,665
Amortization of acquired above and below-market leases	(834)		(140)		(1,748)		14,313
Total rental revenue	$	156,933	$	150,991	$	449,069	$	531,978

Schedule of Sales-type Lease, Lease Income

The components of lease income from sales-type leases during the three and nine months ended September 30, 2024 and 2023 were as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023

Interest income (1)	$	1,127	$	1,113	$	3,369	$	3,328

(1)These amounts are included in Interest expense, net of interest income in our consolidated statements of operations.

Significant Accounting Policies - Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income taxes
Federal, state and local tax provision	$ 1,100	$ 2,500	$ 2,700	$ 5,200
SUMMIT Operator tax (benefit) expense	$ (1,779)	$ 3,735	$ (1,219)	$ 6,881

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482964/270-10-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (ee)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-9

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.7)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-8

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-10

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(9))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (a)
-SubTopic 20
-Topic 740
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482659/740-20-45-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h))
-SubTopic 10
-Topic 235
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

+ Details

Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid- In-Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Retained Deficit	Noncontrolling Interests	Series I Preferred Stock Series I Preferred Stock
Beginning balance at Dec. 31, 2022	$ 4,646,922	$ 656	$ 3,790,358	$ (128,655)	$ 49,604	$ 651,138	$ 61,889	$ 221,932
Beginning balance (in shares) at Dec. 31, 2022		64,380
Increase (Decrease) in Stockholders' Equity
Conversion of common units (shares)		77
Conversion of units in the Operating Partnership for common stock	0
Ending balance at Jun. 30, 2023	4,159,833	$ 656	3,805,704	(128,655)	57,769	135,518	66,909	221,932
Ending balance (in shares) at Jun. 30, 2023		64,387
Beginning balance at Dec. 31, 2022	4,646,922	$ 656	3,790,358	(128,655)	49,604	651,138	61,889	221,932
Beginning balance (in shares) at Dec. 31, 2022		64,380
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(417,138)					(412,679)	(4,459)
Other comprehensive income (loss)	20,012				20,012
Perpetual preferred unit dividends	(11,213)					(11,213)
DRSPP proceeds (in shares)		15
DRSPP proceeds	439		439
Reallocation of noncontrolling interest in the Operating Partnership	(8,072)					(8,072)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)		3
Deferred Compensation Plan and Stock Award, Net	22,961		22,961
Consolidation of joint venture interest	11,714						11,714
Cash distributions to noncontrolling interests	(1,614)						(1,614)
Cash distributions declared	(156,768)					(156,768)
Ending balance at Sep. 30, 2023	4,107,243	$ 656	3,813,758	(128,655)	69,616	62,406	67,530	221,932
Ending balance (in shares) at Sep. 30, 2023		64,398
Beginning balance at Dec. 31, 2022	4,646,922	$ 656	3,790,358	(128,655)	49,604	651,138	61,889	221,932
Beginning balance (in shares) at Dec. 31, 2022		64,380
Ending balance at Dec. 31, 2023	3,855,925	$ 660	3,826,452	(128,655)	17,477	(151,551)	69,610	221,932
Ending balance (in shares) at Dec. 31, 2023		64,726
Beginning balance at Jun. 30, 2023	4,159,833	$ 656	3,805,704	(128,655)	57,769	135,518	66,909	221,932
Beginning balance (in shares) at Jun. 30, 2023		64,387
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(22,023)					(20,229)	(1,794)
Other comprehensive income (loss)	11,847				11,847
Perpetual preferred unit dividends	(3,738)					(3,738)
DRSPP proceeds (in shares)		3
DRSPP proceeds	97		97
Reallocation of noncontrolling interest in the Operating Partnership	3,126					3,126
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)		8
Deferred Compensation Plan and Stock Award, Net	7,957		7,957
Consolidation of joint venture interest	3,266						3,266
Cash distributions to noncontrolling interests	(851)						(851)
Cash distributions declared	(52,271)					(52,271)
Ending balance at Sep. 30, 2023	4,107,243	$ 656	3,813,758	(128,655)	69,616	62,406	67,530	221,932
Ending balance (in shares) at Sep. 30, 2023		64,398
Beginning balance at Dec. 31, 2023	3,855,925	$ 660	3,826,452	(128,655)	17,477	(151,551)	69,610	221,932
Beginning balance (in shares) at Dec. 31, 2023		64,726
Increase (Decrease) in Stockholders' Equity
Net income (loss)	4,765					8,915	(4,150)
Acquisition of subsidiary interest from noncontrolling interest	(5,674)						(5,674)
Other comprehensive income (loss)	(44,785)				(44,785)
Perpetual preferred unit dividends	(11,213)					(11,213)
DRSPP proceeds (in shares)		342
DRSPP proceeds	23,753	$ 3	23,750
Reallocation of noncontrolling interest in the Operating Partnership	(77,400)					(77,400)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)		90
Deferred Compensation Plan and Stock Award, Net	15,886		15,886
Contributions to consolidated joint venture interests	1,823						1,823
Consolidation of joint venture interest	6,678						6,678
Cash distributions to noncontrolling interests	(4,567)						(4,567)
Cash distributions declared	(145,186)					(145,186)
Ending balance at Sep. 30, 2024	3,620,005	$ 663	3,866,088	(128,655)	(27,308)	(376,435)	63,720	221,932
Ending balance (in shares) at Sep. 30, 2024		65,235
Beginning balance at Jun. 30, 2024	3,757,761	$ 660	3,836,751	(128,655)	40,371	(279,763)	66,465	221,932
Beginning balance (in shares) at Jun. 30, 2024		64,814
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(10,526)					(9,541)	(985)
Other comprehensive income (loss)	(67,679)				(67,679)
Perpetual preferred unit dividends	(3,738)					(3,738)
DRSPP proceeds (in shares)		340
DRSPP proceeds	23,633	$ 3	23,630
Conversion of common units (shares)		77
Conversion of units in the Operating Partnership for common stock	0
Reallocation of noncontrolling interest in the Operating Partnership	(34,923)					(34,923)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)		4
Deferred Compensation Plan and Stock Award, Net	5,707		5,707
Cash distributions to noncontrolling interests	(1,760)						(1,760)
Cash distributions declared	(48,470)					(48,470)
Ending balance at Sep. 30, 2024	$ 3,620,005	$ 663	$ 3,866,088	$ (128,655)	$ (27,308)	$ (376,435)	$ 63,720	$ 221,932
Ending balance (in shares) at Sep. 30, 2024		65,235

Debt and Preferred Equity Investments - Schedule of Preferred Equity Investments with an Aggregate Weighted Average Current Yield (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2022
Preferred equity investment
Mortgage loans on real estate, interest rate	6.32%
Carrying Value	$ 293,924	$ 346,745
Allowance for loan loss	$ (13,520)	(13,520)	$ (6,630)
Preferred Equity (4)
Preferred equity investment
Aggregate weighted average current yield	6.55%
Carrying Value	$ 134,474
Preferred Equity (4) \| 625 Madison Avenue
Preferred equity investment
Carrying Value	$ 209,900
Preferred Equity Investments
Preferred equity investment
Mortgage loans on real estate, interest rate	6.55%
Future Funding Obligations	$ 0
Senior Financing	250,000
Allowance for loan loss	0	0
Total after allowance for loan loss	134,474	128,000
Preferred Equity, February 2027
Preferred equity investment
Future Funding Obligations	0
Senior Financing	250,000
Carrying Value	$ 134,474	$ 128,000

Noncontrolling Interests on the Company's Consolidated Financial Statements (Tables)

9 Months Ended

Sep. 30, 2024

Noncontrolling Interest [Abstract]

Schedule of Noncontrolling Interest


	September 30, 2024		December 31, 2023
Balance at beginning of period	$	238,051	$	269,993
Distributions	(10,545)		(14,779)
Issuance of common units	13,927		25,365
Redemption and conversion of common units	(21,977)		(18,589)
Net income (loss)	(166)		(37,465)
Accumulated other comprehensive income (loss) allocation	(3,097)		(1,960)
Fair value adjustment	77,400		15,486
Balance at end of period	$	293,593	$	238,051

Schedule of Preferred Unit Activity

Below is a summary of the preferred units of limited partnership interest in the Operating Partnership as of September 30, 2024:


Issuance	Stated Distribution Rate		Number of Units Authorized	Number of Units Issued	Number of Units Outstanding	Annual Dividend Per Unit(1)		Liquidation Preference Per Unit(2)		Conversion Price Per Unit(3)		Date of Issuance
Series A (4)	6.00	%	109,161	109,161	109,161	$	60.0000	$	1,000.00	$	—	August 2015
Series F	7.00	%	60	60	60	70.0000		1,000.00		29.12		January 2007
Series K	3.50	%	700,000	563,954	341,677	0.8750		25.00		134.67		August 2014
Series L	4.00	%	500,000	378,634	372,634	1.0000		25.00		—		August 2014
Series R	3.50	%	400,000	400,000	400,000	0.8750		25.00		154.89		August 2015
Series S	4.00	%	1,077,280	1,077,280	1,077,280	1.0000		25.00		—		August 2015
Series V (5)	5.00	%	40,000	40,000	40,000	1.2500		25.00		—		May 2019
Series W (6)	(6)		1	1	1	(6)		(6)		(6)		January 2020

(1)Dividends are cumulative, subject to certain provisions.

(2)Units are redeemable at any time at par for cash at the option of the unit holder unless otherwise specified.

(4)Issued through a consolidated subsidiary. The units are redeemable at any time after December 13, 2024 at par for cash at the option of the unit holder.

(5)The Series V Preferred Units are redeemable at any time after January 1, 2025 at par for cash at the option of the unit holder.


	September 30, 2024		December 31, 2023
Balance at beginning of period	$	166,501	$	177,943
Issuance of preferred units	—		—
Redemption of preferred units	—		(11,700)
Dividends paid on preferred units	(3,916)		(6,271)
Accrued dividends on preferred units	4,146		6,529
Balance at end of period	$	166,731	$	166,501

Segment Information (Tables)

9 Months Ended

Sep. 30, 2024

Segment Reporting [Abstract]

Schedule of Selected Results of Operations and Selected Asset Information


	Real Estate Segment		SUMMIT Segment		Debt and Preferred Equity Segment		Total Company
Total revenues
Three months ended:
September 30, 2024	$	183,139	$	36,437	$	10,115	$	229,691
September 30, 2023	$	165,428	$	35,069	$	9,689	$	210,186
Nine months ended:
September 30, 2024	$	522,041	$	94,643	$	23,709	$	640,393
September 30, 2023	$	591,117	$	83,020	$	27,849	$	701,986
Net income (loss)
Three months ended:
September 30, 2024	$	(18,326)	$	(362)	$	9,424	$	(9,264)
September 30, 2023	$	(20,385)	$	(1,897)	$	588	$	(21,694)
Nine months ended:
September 30, 2024	$	(11,745)	$	11,202	$	11,627	$	11,084
September 30, 2023	$	(444,904)	$	(1,101)	$	6,726	$	(439,279)
Total assets
As of:
September 30, 2024	$	8,707,930	$	478,288	$	1,029,854	$	10,216,072
December 31, 2023	$	8,707,147	$	464,799	$	359,235	$	9,531,181

Deferred Costs (Tables)

9 Months Ended

Sep. 30, 2024

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Schedule of Components of Deferred Costs

Deferred costs as of September 30, 2024 and December 31, 2023 consisted of the following (in thousands):


	September 30, 2024		December 31, 2023
Deferred leasing costs	$	409,205	$	399,224
Less: accumulated amortization	(303,559)		(287,761)
Deferred costs, net	$	105,646	$	111,463

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings As of September 30, 2024, the Company and the Operating Partnership were not involved in any material litigation nor, to management's knowledge, was any material litigation threatened against us or our portfolio which if adversely determined could have a material adverse impact on us. Environmental Matters Our management believes that the properties are in compliance in all material respects with applicable Federal, state and local ordinances and regulations regarding environmental issues. Management is not aware of any environmental liability that it believes would have a materially adverse impact on our financial position, results of operations or cash flows. Management is unaware of any instances in which it would incur significant environmental cost if any of our properties were sold.

Fair Value Measurements

9 Months Ended

Sep. 30, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

We are required to disclose fair value information with regard to certain of our financial instruments, whether or not recognized in the consolidated balance sheets, for which it is practical to estimate fair value. The FASB guidance defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. We measure and/or disclose the estimated fair value of certain financial assets and liabilities based on a hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity and the reporting entity’s own assumptions about market participant assumptions. This hierarchy consists of three broad levels: Level 1 - quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity can access at the measurement date; Level 2 - inputs other than quoted prices included within Level 1, that are observable for the asset or liability, either directly or indirectly; and Level 3 - unobservable inputs for the asset or liability that are used when little or no market data is available. We follow this hierarchy for our assets and liabilities measured at fair value on a recurring and nonrecurring basis. In instances in which the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level of input that is significant to the fair value measurement in its entirety. Our assessment of the significance of the particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability.


	September 30, 2024
	Total		Level 1		Level 2		Level 3
Assets:
Marketable securities available-for-sale	$	16,522	$	—	$	16,522	$	—
Interest rate cap and swap agreements (included in Other assets)	17,026		—		17,026		—
Real estate loans held by consolidated securitization vehicles	586,823		—		586,823		—
Liabilities:
Interest rate cap and swap agreements (included in Other liabilities)	$	29,372	$	—	$	29,372	$	—
Senior obligations of consolidated securitization vehicles	571,711		—		571,711		—
Secured borrowing (1)	237,454		—		—		237,454


	December 31, 2023
	Total		Level 1		Level 2		Level 3
Assets:
Marketable securities available-for-sale	$	9,591	$	—	$	9,591	$	—
Interest rate cap and swap agreements (included in Other assets)	33,456		—		33,456		—

Liabilities:
Interest rate cap and swap agreements (included in Other liabilities)	$	17,108	$	—	$	17,108	$	—

We evaluate real estate investments and debt and preferred equity investments, including intangibles, for potential impairment primarily utilizing cash flow projections that apply, among other things, estimated revenue and expense growth rates, discount rates and capitalization rates, as well as sales comparison approach, which utilizes comparable sales, listings and sales contracts, all of which are classified as Level 3 inputs.

In March 2024, the Company entered into an agreement to acquire its partner's 45.0% interest in the 10 East 53rd Street joint venture. As a result of the contract terms, it was concluded that the joint venture is a VIE in which the Company is the primary beneficiary, and the investment was consolidated in our financial statements. Upon consolidating the entity, the assets and liabilities of the entity were recorded at fair value which resulted in the recognition of a fair value adjustment of ($55.7 million), which is included in Purchase price and other fair value adjustments in the consolidated statements of operations. This fair value was determined using a third-party valuation which primarily utilized cash flow projections that apply, among other things, estimated revenue and expense growth rates, discount rates and capitalization rates, as well as the sales comparison approach, which utilizes comparable sales, listings, and sales contracts. All of which are classified as Level 3 inputs.

Marketable securities classified as Level 1 are derived from quoted prices in active markets. The valuation technique used to measure the fair value of marketable securities classified as Level 2 were valued based on quoted market prices or model driven valuations using the significant inputs derived from or corroborated by observable market data. We do not intend to sell these securities and it is not more likely than not that we will be required to sell the investments before recovery of their amortized cost bases.

The fair value of derivative instruments is based on current market data received from financial sources that trade such instruments and are based on prevailing market data and derived from third party proprietary models based on well-recognized financial principles and reasonable estimates about relevant future market conditions, which are classified as Level 2 inputs.

The senior obligations of consolidated securitization vehicles represent CMBS that are not owned by the Company. A majority of these securities are either traded in the marketplace or are similar to other securities that are traded in the marketplace. As the valuation of these amounts are based upon quoted prices for similar instruments in active markets, we generally utilize third party pricing service providers to determine the fair value. The Company evaluates and assesses the third party pricing by referring to recent trades of similar securities, ratings, subordination levels, current market data and credit issues. The Company maximizes the use of observable inputs over unobservable inputs and uses the value of the senior obligations of consolidated securitization vehicles as an indicator of the fair value of the real estate loans held by consolidated securitization vehicles. Depending on the significance of the fair value inputs used in determining the fair value, these securities are classified in either Level 2 or Level 3 of the fair value hierarchy. As such, these investments may move between Level 2 and Level 3 of the fair value hierarchy if the significant fair value inputs used to price the CMBS become or cease to be observable.

The fair value of our secured borrowing is determined by projecting future cash flows, which takes into consideration various factors including discount rate and exit capitalization rate, as well as related asset performance and local or macro real estate performance. The inputs used in determining the Company's secured borrowing are considered Level 3.

The financial assets and liabilities that are not measured at fair value on our consolidated balance sheets include cash and cash equivalents, restricted cash, accounts receivable, accounts payable and accrued expenses, debt and preferred equity investments, mortgages and other loans payable and other secured and unsecured debt. The carrying amount of cash and cash equivalents, restricted cash, accounts receivable, and accounts payable and accrued expenses reported in our consolidated balance sheets approximates fair value due to the short-term nature of these instruments. The fair value of debt and preferred equity investments, which is classified as Level 3, is estimated by discounting the future cash flows using current interest rates at which similar loans with the same maturities would be made to borrowers with similar credit ratings. The fair value of borrowings, which is classified as Level 3, is estimated by discounting the contractual cash flows of each debt instrument to their present value using adjusted market interest rates, which is provided by a third-party specialist.

The following table provides the carrying value and fair value of these financial instruments as of September 30, 2024 and December 31, 2023 (in thousands):


	September 30, 2024				December 31, 2023
	Carrying Value (1)		Fair Value		Carrying Value (1)		Fair Value

Debt and preferred equity investments	$	293,924	(2)		$	346,745	(2)

Fixed rate debt	$	3,287,898	$	3,252,374	$	3,237,386	$	3,184,338
Variable rate debt (3)	545,900		545,282		270,000		268,787
	$	3,833,798	$	3,797,656	$	3,507,386	$	3,453,125

(1)Amounts exclude net deferred financing costs.

(3)As of September 30, 2024, variable rate debt with a carrying value of $60.9 million and fair value of $60.1 million is included in the Company's alternative strategy portfolio.

Disclosures regarding fair value of financial instruments was based on pertinent information available to us as of September 30, 2024 and December 31, 2023. Such amounts have not been comprehensively revalued for purposes of these financial statements since that date and current estimates of fair value may differ significantly from the amounts presented herein.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
-SubTopic 820
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Consolidated Balance Sheets - USD ($)
$ in Thousands

Sep. 30, 2024

Dec. 31, 2023

Commercial real estate properties, at cost:

Land and land interests

$ 1,134,432

$ 1,092,671

Building and improvements

3,781,403

3,655,624

Building leasehold and improvements

1,374,059

1,354,569

Total commercial real estate properties, at cost

6,289,894

6,102,864

Less: accumulated depreciation

(2,084,755)

(1,968,004)

Total commercial real estate properties, net

4,205,139

4,134,860

Cash and cash equivalents

188,216

221,823

Restricted cash

126,909

113,696

Investments in marketable securities

16,522

9,591

Tenant and other receivables

53,628

33,270

Related party receivables

13,077

12,168

Deferred rents receivable

266,606

264,653

Debt and preferred equity investments, net of discounts and deferred origination fees of $1,618 and $1,630 and allowances of $13,520 and $13,520 in 2024 and 2023, respectively

293,924

346,745

Investments in unconsolidated joint ventures

2,871,683

2,983,313

Deferred costs, net

105,646

111,463

Right-of-use assets - operating leases

870,782

885,929

Real estate loans held by consolidated securitization vehicles (includes $586,823 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

713,218

Other assets

490,722

413,670

Total assets

^[1]

10,216,072

9,531,181

Liabilities

Mortgages and other loans payable, net

1,643,992

1,491,319

Revolving credit facility, net

730,851

554,752

Unsecured term loans, net

1,246,180

1,244,881

Unsecured notes, net

99,872

99,795

Accrued interest payable

22,825

17,930

Senior obligations of consolidated securitization vehicles (includes $571,711 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

603,902

Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

409,844

471,401

Accounts payable and accrued expenses

125,377

153,164

Deferred revenue

154,700

134,053

Lease liability - financing leases

106,518

105,531

Lease liability - operating leases

815,238

827,692

Dividend and distributions payable

20,147

20,280

Security deposits

56,297

49,906

Junior subordinated deferrable interest debentures held by trusts that issued trust preferred securities

100,000

Total liabilities

^[1]

6,135,743

5,270,704

Commitments and contingencies

Noncontrolling interests in Operating Partnership

293,593

238,051

Preferred units

166,731

166,501

Equity

Series I Preferred Stock, $0.01 par value, $25.00 liquidation preference, 9,200 issued and outstanding at both September 30, 2024 and December 31, 2023

221,932

Common stock, $0.01 par value, 160,000 shares authorized and 66,295 and 65,786 issued and outstanding at September 30, 2024 and December 31, 2023, respectively (including 1,060 and 1,060 shares held in treasury at September 30, 2024 and December 31, 2023, respectively)

663

660

Additional paid-in-capital

3,866,088

3,826,452

Treasury stock at cost

(128,655)

Accumulated other comprehensive (loss) income

(27,308)

17,477

Retained deficit

(376,435)

(151,551)

Total SL Green stockholders' equity

3,556,285

3,786,315

Noncontrolling interests in other partnerships

63,720

69,610

Total equity

3,620,005

3,855,925

Total liabilities and equity

$ 10,216,072

$ 9,531,181

[1]

Debt and Preferred Equity Investments (Tables)

9 Months Ended

Sep. 30, 2024

Investments, Debt and Equity Securities [Abstract]

Schedule of Activity in Debt and Preferred Equity Investments

Below is a summary of the activity in our consolidated debt and preferred equity investments for the nine months ended September 30, 2024 and the twelve months ended December 31, 2023 (in thousands):


	September 30, 2024		December 31, 2023
Balance at beginning of year (1)	$	346,745	$	623,280
Debt investment originations/fundings/accretion (2)	5,334		72,160
Preferred equity investment originations/accretion (2) (3)	6,474		8,142
Redemptions/sales/syndications/equity ownership/amortization	(64,629)		(349,947)
Net change in loan loss reserves	—		(6,890)
Balance at end of period (1) (4)	$	293,924	$	346,745

(1)Net of unamortized fees, discounts, and premiums.

(2)Accretion includes amortization of fees and discounts and paid-in-kind investment income.

(4)Includes two investments with a total carrying value of $49.8 million that are included in the Company's alternative strategy portfolio.

Schedule of Debt and Preferred Equity Investments

Below is a summary of our consolidated debt and preferred equity investments as of September 30, 2024 (dollars in thousands):


	Floating Rate					Fixed Rate					Total Carrying Value			Senior Financing		Maturity (2)
Type	Carrying Value		Face Value		Interest Rate (1)	Carrying Value		Face Value		Interest Rate


Mezzanine Debt	$	109,450	$	109,604	S + 5.00% - 12.11%	$	50,000	$	50,000	8.00% - 8.40%	$	159,450	(3)	$	804,021	2024 - 2029
Preferred Equity (4)	—		—		—	134,474		134,474		6.5%	134,474			250,000		2027
Balance at end of period	$	109,450	$	109,604		$	184,474	$	184,474		$	293,924		$	1,054,021

(1)Floating interest rates are presented with the stated spread over Term SOFR ("S").

(2)Excludes available extension options to the extent they have not been exercised as of the date of this filing.

(3)Includes two investments with a total carrying value of $49.8 million that are included in the Company's alternative strategy portfolio.

Schedule of Roll Forward of our Total Allowance for Loan Losses

The following table is a roll forward of our total allowance for loan losses for the nine months ended September 30, 2024 and the twelve months ended December 31, 2023 (in thousands):


	September 30, 2024		December 31, 2023
Balance at beginning of year	$	13,520	$	6,630



Current period provision for loan loss	—		6,890

Balance at end of period (1)	$	13,520	$	13,520

Schedule of Carrying Value of Debt and Preferred Equity Investment Portfolio by Year of Origination and Risk Rating


Risk Rating	September 30, 2024		December 31, 2023
1 - Low Risk Assets - Low probability of loss	$	154,474	$	210,333
2 - Watch List Assets - Higher potential for loss (1)	139,450		136,412
3 - High Risk Assets - Loss more likely than not	—		—
	$	293,924	$	346,745

(1)Includes two investments with a total carrying value of $49.8 million that are included in the Company's alternative strategy portfolio.


	As of September 30, 2024
Risk Rating	2024 (1)		2023 (1)		2022 (1)		Prior (1)			Total
1 - Low Risk Assets - Low probability of loss	$	—	$	—	$	—	$	154,474		$	154,474
2 - Watch List Assets - Higher potential for loss	—		—		—		139,450		(2)	139,450
3 - High Risk Assets - Loss more likely than not	—		—		—		—			—
	$	—	$	—	$	—	$	293,924		$	293,924

(1)Year in which the investment was originated or acquired by us or in which a material modification occurred.

(2)Includes two investments with a total carrying value of $49.8 million that are included in the Company's alternative strategy portfolio.

Schedule of Debt Investments with an Aggregate Weighted Average Current Yield


Loan Type	September 30, 2024 Future Funding Obligations		September 30, 2024 Senior Financing		September 30, 2024 Carrying Value (1)		December 31, 2023 Carrying Value (1)		Maturity Date (2)
Fixed Rate Investments:
Mezzanine Loan (3) (4) (6)	$	—	$	105,000	$	13,366	$	13,366	October 2024
Mezzanine Loan	—		95,000		30,000		30,000		January 2025
Mezzanine Loan	—		85,000		20,000		20,000		December 2029
Total fixed rate	$	—	$	285,000	$	63,366	$	63,366
Floating Rate Investments:
Mezzanine Loan (5) (6)	$	—	$	275,000	$	50,000	$	50,000	April 2023
Mezzanine Loan	—		54,000		8,620		8,243		January 2025
Mezzanine Loan	8,099		190,021		50,984		48,323		January 2026
Mezzanine Loan	—		—		—		62,333		May 2024
Total floating rate	$	8,099	$	519,021	$	109,604	$	168,899
Allowance for loan loss	$	—	$	—	$	(13,520)	$	(13,520)
Total	$	8,099	$	804,021	$	159,450	$	218,745

(1)Carrying value is net of discounts, premiums, original issue discounts and deferred origination fees.

(2)Represents contractual maturity, excluding any extension options to the extent they have not been exercised as of the date of this filing.

(6)Included in the Company's alternative strategy portfolio.

Schedule of Preferred Equity Investments with an Aggregate Weighted Average Current Yield


Type	September 30, 2024 Future Funding Obligations		September 30, 2024 Senior Financing		September 30, 2024 Carrying Value (1)		December 31, 2023 Carrying Value (1)		Mandatory Redemption (2)
Preferred Equity	$	—	$	250,000	$	134,474	$	128,000	February 2027

Allowance for loan loss	$	—	$	—	$	—	$	—
Total	$	—	$	250,000	$	134,474	$	128,000

(1)Carrying value is net of deferred origination fees.

(2)Represents contractual redemption, excluding any unexercised extension options.

Noncontrolling Interests on the Company's Consolidated Financial Statements - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Issuance of common units			$ 1,823
Redemption and conversion of common units			(5,674)
Net income (loss)		$ (1,574)	(166)	$ (27,493)
Accumulated other comprehensive income (loss) allocation	$ (4,717)	771	$ (3,097)	1,425
SL Green Operating Partnership
Organization
Number of units of operating partnership owned by the noncontrolling interest unit holders (shares)	4,474,406		4,474,406		3,949,448
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Issuance of common units			$ 1,823
Redemption and conversion of common units			(5,674)
Net income (loss)	$ (914)		(166)
Accumulated other comprehensive income (loss) allocation	$ (4,717)	$ 771	$ (3,097)	1,425	$ (1,960)
SL Green Operating Partnership \| Series A
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Stated Distribution Rate			6.00%
Number of units authorized (in shares)	109,161		109,161
Number of units issued (in shares)	109,161		109,161
Number of units outstanding (in shares)	109,161		109,161
Annual dividend per unit (in dollars per share)			$ 60.0000
Liquidation preference per unit (in dollars per share)	$ 1,000		1,000
Conversion price per unit (in dollars per share)	$ 0		$ 0
SL Green Operating Partnership \| Series F
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Stated Distribution Rate			7.00%
Number of units authorized (in shares)	60		60
Number of units issued (in shares)	60		60
Number of units outstanding (in shares)	60		60
Annual dividend per unit (in dollars per share)			$ 70.0000
Liquidation preference per unit (in dollars per share)	$ 1,000		1,000
Conversion price per unit (in dollars per share)	$ 29.12		$ 29.12
SL Green Operating Partnership \| Series K
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Stated Distribution Rate			3.50%
Number of units authorized (in shares)	700,000		700,000
Number of units issued (in shares)	563,954		563,954
Number of units outstanding (in shares)	341,677		341,677
Annual dividend per unit (in dollars per share)			$ 0.8750
Liquidation preference per unit (in dollars per share)	$ 25.00		25.00
Conversion price per unit (in dollars per share)	$ 134.67		$ 134.67
SL Green Operating Partnership \| Series L
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Stated Distribution Rate			4.00%
Number of units authorized (in shares)	500,000		500,000
Number of units issued (in shares)	378,634		378,634
Number of units outstanding (in shares)	372,634		372,634
Annual dividend per unit (in dollars per share)			$ 1.0000
Liquidation preference per unit (in dollars per share)	$ 25.00		25.00
Conversion price per unit (in dollars per share)	$ 0		$ 0
SL Green Operating Partnership \| Series R
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Stated Distribution Rate			3.50%
Number of units authorized (in shares)	400,000		400,000
Number of units issued (in shares)	400,000		400,000
Number of units outstanding (in shares)	400,000		400,000
Annual dividend per unit (in dollars per share)			$ 0.8750
Liquidation preference per unit (in dollars per share)	$ 25.00		25.00
Conversion price per unit (in dollars per share)	$ 154.89		$ 154.89
SL Green Operating Partnership \| Series S
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Stated Distribution Rate			4.00%
Number of units authorized (in shares)	1,077,280		1,077,280
Number of units issued (in shares)	1,077,280		1,077,280
Number of units outstanding (in shares)	1,077,280		1,077,280
Annual dividend per unit (in dollars per share)			$ 1.0000
Liquidation preference per unit (in dollars per share)	$ 25.00		25.00
Conversion price per unit (in dollars per share)	$ 0		$ 0
SL Green Operating Partnership \| Series V
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Stated Distribution Rate			5.00%
Number of units authorized (in shares)	40,000		40,000
Number of units issued (in shares)	40,000		40,000
Number of units outstanding (in shares)	40,000		40,000
Annual dividend per unit (in dollars per share)			$ 1.2500
Liquidation preference per unit (in dollars per share)	$ 25.00		25.00
Conversion price per unit (in dollars per share)	$ 0		$ 0
SL Green Operating Partnership \| Series W
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Number of units authorized (in shares)	1		1
Number of units issued (in shares)	1		1
Number of units outstanding (in shares)	1		1
Preferred stock, dividend, multiplier per common unit distribution			1,350
Partnership Interest
Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership
Balance at beginning of period			$ 238,051	$ 269,993	269,993
Distributions			(10,545)		(14,779)
Issuance of common units			13,927		25,365
Redemption and conversion of common units			(21,977)		(18,589)
Net income (loss)			(166)		(37,465)
Fair value adjustment			77,400		15,486
Balance at end of period	$ 293,593		$ 293,593		$ 238,051
Operating Partnership \| SL Green Operating Partnership
Organization
Noncontrolling interest in the operating partnership (as a percent)	6.42%		6.42%		5.75%

Significant Accounting Policies (Policies)	9 Months Ended
Significant Accounting Policies (Policies)	Sep. 30, 2024
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include our accounts and those of our subsidiaries, which are wholly-owned or controlled by us. Entities which we do not control through our voting interest, but have significant influence over, and entities which are variable interest entities, but where we are not the primary beneficiary, are accounted for under the equity method. See Note 5, "Debt and Preferred Equity Investments" and Note 6, "Investments in Unconsolidated Joint Ventures." We consolidate a VIE in which we are considered the primary beneficiary. The primary beneficiary is the entity that has (i) the power to direct the activities that most significantly impact the entity's economic performance and (ii) the obligation to absorb losses of the VIE or the right to receive benefits from the VIE that could be significant to the VIE. All significant intercompany balances and transactions have been eliminated.
Investment in Commercial Real Estate Properties	Investment in Commercial Real Estate Properties We allocate the purchase price of real estate to land and building (inclusive of tenant improvements) and, if determined to be material, intangibles, such as the value of above- and below-market leases and origination costs associated with the in-place leases. We depreciate the amount allocated to building (inclusive of tenant improvements) over their estimated useful lives, which generally range from 3 years to 40 years. We amortize the amount allocated to the above- and below-market leases over the remaining term of the associated lease, which generally range from 1 year to 15 years, and record it as either an increase (in the case of below-market leases) or a decrease (in the case of above-market leases) to rental income. We amortize the amount allocated to the values associated with in-place leases over the expected term of the associated lease, which generally ranges from 1 year to 15 years. If a tenant vacates its space prior to the contractual termination of the lease and no rental payments are being made on the lease, any unamortized balance of the related intangible will be written off. Origination costs are amortized as an expense over the remaining life of the lease and tenant improvements are amortized over the shorter of the remaining life of the lease or useful life of the improvement (or charged against earnings if the lease is terminated prior to its contractual expiration date). When allocating the purchase price of real estate, we assess fair value of the leases based on estimated cash flow projections that utilize appropriate discount rates and available market information. Estimates of future cash flows are based on a number of factors including the historical operating results, known trends, and market/economic conditions that may affect the property. To the extent acquired leases contain fixed rate renewal options that are below-market and determined to be material, we amortize such below-market lease value into rental income over the renewal period. The Company classifies those leases under which the Company is the lessee at lease commencement as finance or operating leases. Leases qualify as finance leases if the lease transfers ownership of the asset at the end of the lease term, the lease grants an option to purchase the asset that we are reasonably certain to exercise, the lease term is for a major part of the remaining economic life of the asset, or the present value of the lease payments equals or exceeds substantially all of the fair value of the underlying asset. Leases that do not qualify as finance leases are deemed to be operating leases. At lease commencement the Company records a lease liability which is measured as the present value of the lease payments and a right of use asset which is measured as the amount of the lease liability and any initial direct costs incurred. The Company applies a discount rate to determine the present value of the lease payments. If the rate implicit in the lease is known, the Company uses that rate. If the rate implicit in the lease is not known, the Company uses a discount rate reflective of the Company’s collateralized borrowing rate given the term of the lease. To determine the discount rate, the Company employs a third-party specialist to develop an analysis based primarily on the observable borrowing rates of the Company, other REITs, and other corporate borrowers with long-term borrowings. On the consolidated statements of operations, operating leases are expensed through operating lease rent while financing leases are expensed through amortization and interest expense. When applicable, the Company combines the consideration for lease and non-lease components in the calculation of the value of the lease obligation and right-of-use asset.
Cash and Cash Equivalents	Cash and Cash Equivalents We consider all highly liquid investments with maturity of three months or less when purchased to be cash equivalents.
Restricted Cash	Restricted Cash Restricted cash primarily consists of security deposits held on behalf of our tenants, interest reserves, as well as capital improvement and real estate tax escrows required under certain loan agreements.
Investment in Marketable Securities	Investment in Marketable Securities At acquisition, we designate a debt security as held-to-maturity, available-for-sale, or trading. As of September 30, 2024, we did not have any debt securities designated as held-to-maturity or trading. We account for our available-for-sale securities at fair value pursuant to ASC 820-10, with the net unrealized gains or losses reported as a component of accumulated other comprehensive income or loss. The cost of marketable securities sold and the amount reclassified out of accumulated other comprehensive income into earnings is determined using the specific identification method. Credit losses are recognized in accordance with ASC 326. We account for equity marketable securities at fair value pursuant to ASC 820-10, with the net unrealized gains or losses reported in net income.
Investment in CMBS Securitization Trusts	Investment in CMBS Securitization Trusts We may acquire securities in CMBS securitization trusts and, which in certain cases, we may be contracted to provide special servicing activities for these trusts. In certain cases, we may acquire the controlling class of the trust and we may have the right to name and remove the special servicer for these trusts. These circumstances may result in our consolidating the securitization trusts on our financial statements. We evaluate all of our positions and special servicer appointments for consolidation, which are considered to be VIEs to the Company. As the special servicer, we provide services on defaulted loans within the trusts as permitted by the underlying contractual agreements. We receive a fee in exchange for these services. The rights provided to us as special servicer give us the ability to direct activities that could significantly impact the trust's economic performance, which requires consolidation of the securitization trust unless a third party has the right to unilaterally remove us as special servicer without cause. In such instances where we can be removed as special servicer without cause, we do not have the power to direct activities that most significantly impact the trust's economic performance and would not consolidate the securitization trust. For CMBS securitization trusts in which we are determined to be the primary beneficiary, we consolidate the securitization trusts on our consolidated balance sheets. The consolidation of such securitization trusts results in a gross presentation of the underlying collateral loans as assets as well as the senior CMBS positions owned by third parties, which are presented as liabilities on our consolidated balance sheets. The assets of the consolidated securitization trust can only be used to satisfy the liabilities of that securitization and are not available to the Company for any other purpose. Additionally, the senior CMBS securitization trust obligations can only be satisfied through repayment of the underlying collateral loans as they do not have any recourse to the Company or our assets. The Company has not provided any guarantees with respect to the performance or repayment of the senior CMBS obligations. While consolidation of the securitization trust increases the gross presentation of our consolidated balance sheets, it does not impact the economic exposure or performance of the Company as it is limited to that of the actual investment in the CMBS securitization trust, and not the consolidated senior obligations.
Investments in Unconsolidated Joint Ventures	Investments in Unconsolidated Joint Ventures We assess our investments in unconsolidated joint ventures for recoverability and if it is determined that a loss in value of the investment is other than temporary, we write down the investment to its fair value. We evaluate our equity investments for impairment based on each joint ventures' actual and projected cash flows. Aside from charges noted in Note 6, "Investments in Unconsolidated Joint Ventures," we do not believe that the values of any of our equity investments were impaired at September 30, 2024.
Deferred Lease Costs and Lease Classification	Deferred Lease Costs Deferred lease costs consist of incremental fees and direct costs that would not have been incurred if the lease had not been obtained and are amortized on a straight-line basis over the related lease term. Lease Classification Lease classification for leases under which the Company is the lessor is evaluated at lease commencement and leases not classified as sales-type leases or direct financing leases are classified as operating leases. Leases qualify as sales-type leases if the contract includes either transfer of ownership clauses, certain purchase options, a lease term representing a major part of the economic life of the asset, or the present value of the lease payments and residual guarantees provided by the lessee exceeds substantially all of the fair value of the asset. Additionally, leasing an asset so specialized that it is not deemed to have any value to the Company at the end of the lease term may also result in classification as a sales-type lease. Leases qualify as direct financing leases when the present value of the lease payments and residual value guarantees provided by the lessee and unrelated third parties exceeds substantially all of the fair value of the asset and collection of the payments is probable.
Revenue Recognition	Revenue Recognition Rental revenue for operating leases is recognized on a straight-line basis over the term of the lease. Rental revenue recognition commences when the leased space is available for its intended use by the lessee. To determine whether the leased space is available for its intended use by the lessee, management evaluates whether we or the tenant are the owner of tenant improvements for accounting purposes. When management concludes that we are the owner of tenant improvements, rental revenue recognition begins when the tenant takes possession of the finished space, which is when such tenant improvements are substantially complete. In certain instances, when management concludes that we are not the owner of tenant improvements, rental revenue recognition begins when the tenant takes possession of or controls the space. The excess of rents recognized over amounts contractually due pursuant to the underlying leases are included in deferred rents receivable on the consolidated balance sheets. In addition to base rent, our tenants also generally will pay variable rent, which represents their pro rata share of increases in real estate taxes and certain operating expenses for the building over a base year. In some leases, in lieu of paying additional rent based upon increases in certain building operating expenses, the tenant will pay additional rent based upon increases in the wage rate paid to porters over the porters' wage rate in effect during a base year or increases in the consumer price index over the index value in effect during a base year. In addition, many of our leases contain fixed percentage increases over the base rent to cover escalations. Electricity is most often supplied by the landlord either on a sub-metered basis, or rent inclusion basis (i.e., a fixed fee is included in the rent for electricity, which amount may increase based upon increases in electricity rates or increases in electrical usage by the tenant). Base building services other than electricity (such as heat, air conditioning and freight elevator service during business hours, and base building cleaning) are typically provided at no additional cost, with the tenant paying additional rent only for services which exceed base building services or for services which are provided outside normal business hours. These escalations are based on actual expenses incurred in the prior calendar year. If the expenses in the current year are different from those in the prior year, then during the current year, the escalations will be adjusted to reflect the actual expenses for the current year. Rental revenue is recognized if collectability is probable. If collectability of substantially all of the lease payments is assessed as not probable, any difference between the rental revenue recognized to date and the lease payments that have been collected is recognized as a current-period adjustment to rental revenue. A subsequent change in the assessment of collectability to probable may result in a current-period adjustment to rental revenue for any difference between the rental revenue that would have been recognized if collectability had always been assessed as probable and the rental revenue recognized to date. The Company provides its tenants with certain customary services for lease contracts such as common area maintenance and general security. We have elected to combine the non-lease components with the lease components of our operating lease agreements and account for them as a single lease component in accordance with ASC 842. We record a gain or loss on sale of real estate assets when we no longer have a controlling financial interest in the entity owning the real estate, a contract exists with a third party and that third party has control of the assets acquired. Investment income on debt and preferred equity investments is accrued based on the contractual terms of the instruments and when it is deemed collectible. Some debt and preferred equity investments provide for accrual of interest at specified rates, which differ from current payment terms. Interest is recognized on such loans at the accrual rate subject to management's determination that accrued interest is collectible. If management cannot make this determination, interest income above the current pay rate is recognized only upon actual receipt. Deferred origination fees, original issue discounts and loan origination costs, if any, are recognized as an adjustment to interest income over the terms of the related investments using the effective interest method. Fees received in connection with loan commitments are also deferred until the loan is funded and are then recognized over the term of the loan as an adjustment to yield. Discounts or premiums associated with the purchase of loans are amortized or accreted into interest income as a yield adjustment on the effective interest method based on expected cash flows through the expected maturity date of the related investment. If we purchase a debt or preferred equity investment at a discount, intend to hold it until maturity and expect to recover the full value of the investment, we accrete the discount into income as an adjustment to yield over the term of the investment. If we purchase a debt or preferred equity investment at a discount with the intention of foreclosing on the collateral, we do not accrete the discount. For debt investments acquired at a discount for credit quality, the difference between contractual cash flows and expected cash flows at acquisition is not accreted. Anticipated exit fees, the collection of which is expected, are also recognized over the term of the loan as an adjustment to yield. We consider a debt and preferred equity investment to be past due when amounts contractually due have not been paid. Debt and preferred equity investments are placed on a non-accrual status at the earlier of the date at which payments become 90 days past due or when, in the opinion of management, a full recovery of interest income becomes doubtful. Interest income recognition is resumed on any debt or preferred equity investment that is on non-accrual status when such debt or preferred equity investment becomes contractually current and performance is demonstrated to be resumed. We may syndicate a portion of the loans that we originate or sell the loans individually. When a transaction meets the criteria for sale accounting, we recognize gain or loss based on the difference between the sales price and the carrying value of the loan sold. Any related unamortized deferred origination fees, original issue discounts, loan origination costs, discounts or premiums at the time of sale are recognized as an adjustment to the gain or loss on sale, which is included in investment income on the consolidated statement of operations. Any fees received at the time of sale or syndication are recognized as part of investment income. Asset management fees are recognized on a straight-line basis over the term of the asset management agreement. Revenues from the sale of SUMMIT tickets are recognized upon admission or ticket expirations. Deferred revenue related to unused and unexpired tickets as of September 30, 2024 and December 31, 2023 was $3.8 million and $2.6 million, respectively, and is included in Deferred revenue on the consolidated balance sheets.
Debt and Preferred Equity Investments	Debt and Preferred Equity Investments Debt and preferred equity investments are presented at the net amount expected to be collected in accordance with ASC 326. An allowance for loan losses is deducted from the amortized cost basis of the financial assets to present the net carrying value at the amount expected to be collected through the expected maturity date of such investments. The expense for loan loss and other investment reserves is the charge to earnings to adjust the allowance for loan losses to the appropriate level. Amounts are written off from the allowance when we de-recognize the related investment either as a result of a sale of the investment or acquisition of equity interests in the collateral. The Company evaluates the amount expected to be collected based on current market and economic conditions, historical loss information, and reasonable and supportable forecasts. The Company's assumptions are derived from both internal data and external data which may include, among others, governmental economic projections for the New York City Metropolitan area, public data on recent transactions and filings for securitized debt instruments. This information is aggregated by asset class and adjusted for duration. Based on these inputs, loans are evaluated at the individual asset level. In certain instances, we may also use a probability-weighted model that considers the likelihood of multiple outcomes and the amount expected to be collected for each outcome. The evaluation of the possible credit deterioration associated with the performance and/or value of the underlying collateral property as well as the financial and operating capability of the borrower/sponsor requires significant judgment, which include both asset level and market assumptions over the relevant time period. In addition, quarterly, the Company assigns each loan a risk rating. Based on a 3-point scale, loans are rated “1” through “3,” from lower risk to higher risk, which ratings are defined as follows: 1 - Low Risk Assets - Low probability of loss, 2 - Watch List Assets - Higher potential for loss, 3 - High Risk Assets - Loss more likely than not. Loans with risk ratings of 2 or above are evaluated to determine whether the expected risk of loss is appropriately captured through the combination of our expectations of current conditions, historical loss information and supportable forecasts described above or whether risk characteristics specific to the loan warrant the use of a probability-weighted model. Financing investments that are classified as held for sale are carried at the expected amount to be collected or fair market value using available market information obtained through consultation with dealers or other originators of such investments as well as discounted cash flow models based on Level 3 data pursuant to ASC 820-10. As circumstances change, management may conclude not to sell an investment designated as held for sale. In such situations, the investment will be reclassified at its expected amount to be collected. Other financing receivables that are included in balance sheet line items other than the Debt and preferred equity investments line are also measured at the net amount expected to be collected. Accrued interest receivable amounts related to these debt and preferred equity investment and other financing receivables are recorded at the net amount expected to be collected within Other assets in the consolidated balance sheets. Accrued interest receivables that are written off are recognized as an expense in loan loss and other investment reserves.
Income Taxes	Income Taxes SL Green is taxed as a REIT under Section 856(c) of the Code. As a REIT, SL Green generally is not subject to Federal income tax. To maintain its qualification as a REIT, SL Green must distribute at least 90% of its REIT taxable income to its stockholders and meet certain other requirements. If SL Green fails to qualify as a REIT in any taxable year, SL Green will be subject to Federal income tax on its taxable income at regular corporate rates. SL Green may also be subject to certain state, local and franchise taxes. Under certain circumstances, Federal income and excise taxes may be due on its undistributed taxable income. The Operating Partnership is a partnership and, as a result, all income and losses of the partnership are allocated to the partners for inclusion in their respective income tax returns. The only provision for income taxes included in the consolidated statements of operations relates to the Operating Partnership’s consolidated taxable REIT subsidiaries. The Operating Partnership may also be subject to certain state, local and franchise taxes. We have elected, and may elect in the future, to treat certain of our corporate subsidiaries as taxable REIT subsidiaries, or TRSs. In general, TRSs may perform non-customary services for the tenants of the Company, hold assets that we cannot hold directly and generally may engage in any real estate or non-real estate related business. The TRSs generate income, resulting in Federal, state and local corporate tax liability for these entities. During the three and nine months ended September 30, 2024, we recorded Federal, state and local tax provisions totaling $1.1 million and $2.7 million, respectively, for these entities. During the three and nine months ended September 30, 2023, we recorded Federal, state and local tax provisions totaling $2.5 million and $5.2 million, respectively, for these entities. SUMMIT is held in a TRS and pays Federal, state and local taxes. During the three and nine months ended September 30, 2024, we recorded Federal, state and local tax benefits for SUMMIT of $1.8 million and $1.2 million, respectively. During the three and nine months ended September 30, 2023, we recorded Federal, state and local tax expense for SUMMIT of $3.7 million and $6.9 million, respectively. We follow a two-step approach for evaluating uncertain tax positions. Recognition (step one) occurs when an enterprise concludes that a tax position, based solely on its technical merits, is more-likely-than-not to be sustained upon examination. Measurement (step two) determines the amount of benefit that is more-likely-than-not to be realized upon settlement. Derecognition of a tax position that was previously recognized would occur when a company subsequently determines that a tax position no longer meets the more-likely-than-not threshold of being sustained. The use of a valuation allowance as a substitute for derecognition of tax positions is prohibited.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash investments, debt and preferred equity investments and accounts receivable. We place our cash investments with high quality financial institutions. The collateral securing our debt and preferred equity investments is located in New York City. See Note 5, "Debt and Preferred Equity Investments." We perform initial and ongoing evaluations of the credit quality of our tenants and require most tenants to provide security deposits or letters of credit. Though these security deposits and letters of credit are insufficient to meet the total value of a tenant's lease obligation, they are a measure of good faith and a potential source of funds to offset the economic costs associated with lost revenue from that tenant and the costs associated with re-tenanting a space.
Reclassification	Reclassification Certain prior year balances have been reclassified to conform to our current year presentation. Beginning in the second quarter of 2024, we reclassified amounts recorded for certain right-of-use assets classified as operating leases from a gross presentation above accumulated depreciation to a net presentation below accumulated depreciation in our consolidated balance sheets. This includes reclassifying the related amortization that was previously included in the accumulated depreciation. We believe this presentation enhances the Company's financial statements. As of December 31, 2023, SUMMIT met the criteria of a reportable operating segment pursuant to the guidance in ASC 280. Accordingly, we reclassified SUMMIT Operator revenue, SUMMIT Operator expenses, and SUMMIT Operator tax expense to separate financial statement line items in our consolidated statements of operations. These items were previously presented on a net basis in Other income. Additionally, the depreciation and amortization of SUMMIT assets are included in Depreciation and amortization in our consolidated statements of operations. Prior period balances have been reclassified to conform to the current period presentation.
Accounting Standards Updates	Accounting Standards Updates In December 2023, the FASB issued ASU No. 2023-09 Income Taxes (Topic 740) - Improvements to Income Tax Disclosures. The objective of the amendments in ASU 2023-09 related to the rate reconciliation and income taxes paid disclosures are to improve transparency of income tax disclosures by requiring consistent categories and greater disaggregation of information in the rate reconciliation, and income taxes paid disaggregated by jurisdiction. The amendment will require that public entities on an annual basis disclose specific categories in the rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. Additionally, the amendment will require that all entities disclose on an annual basis the amount of taxes paid (net of refunds received) disaggregated by federal, state and foreign taxes as well as disaggregated by individual jurisdictions that meet a quantitative threshold. ASU 2023-09 is effective prospectively for annual periods beginning after December 15, 2024. Early adoption and retrospective application is permitted. We are currently evaluating the impact of the adoption of ASU 2023-09 on our consolidated financial statements, but do not believe the adoption of this standard will have a material impact on our consolidated financial statements. In November 2023, the FASB issued ASU No. 2023-07 Segment Reporting (Topic 280) - Improvements to Reportable Segment Disclosures. ASU 2023-07 amends the reportable segment disclosure requirements to enhance disclosures about significant segment expenses. The objective of the amendment is to improve financial reporting by requiring disclosure of incremental segment information on an annual and interim basis for all public entities to enable investors to develop more decision-useful financial analyses. The amendment will require that a public entity disclose, on an annual and interim basis, significant segment expenses that are regularly provided to the chief operating decision maker ("CODM") and included within each reported measure of segment profit or loss (collectively referred to as the "significant expense principle"). Additionally, the amendment will require an entity to disclose an amount for "other segment items" by reportable segment and a description of its composition as well as require annual disclosures about a reportable segment's profit or loss and assets currently required by Topic 280 in interim periods. Lastly, the amendment will require a public entity to disclose the title and position of the CODM and an explanation of how the CODM uses the reported measures of segment profit or loss in assessing segment performance and deciding to allocate resources. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted and should be applied retrospectively to all prior periods presented in the financial statements. We are currently evaluating the impact of the adoption of ASU 2023-07 on our consolidated financial statements, but do not believe the adoption of this standard will have a material impact on our consolidated financial statements. In August 2023, the FASB issued ASU No. 2023-05 Business Combinations - Joint Venture Formations (Subtopic 805-60) Recognition and Initial Measurement. ASU 2023-05 addresses the accounting for contributions made to a joint venture, upon formation, in a joint venture's separate financial statements. The objectives of the amendments are to provide decision-useful information to investors and other allocators of capital in a joint venture's financial statements and reduce diversity in practice. The amendments require that a joint venture apply the following key adaptations from the business combinations guidance upon formation: (i) a joint venture is the formation of a new entity without an accounting acquirer, (ii) a joint venture measures its identifiable net assets and goodwill, if any, at the formation date, (iii) initial measurement of a joint venture's total net assets is equal to the fair value of 100 percent of the joint venture's equity, and (iv) a joint venture provides relevant disclosures. ASU 2023-05 is effective prospectively for all joint venture formations with a formation date on or after January 1, 2025, with early adoption permitted in any interim or annual period in which financial statements have not yet been issued, either prospectively or retrospectively. We are currently evaluating the impact of the adoption of ASU 2023-05 on our consolidated financial statements, but do not believe the adoption of this standard will have a material impact on our consolidated financial statements. In March 2020, the FASB issued ASU No. 2020-04 Reference Rate Reform (Topic 848) Facilitation of the Effects of Reference Rate Reform on Financial Reporting and then in January 2021, the FASB issued ASU No. 2021-01. The amendments provide practical expedients for reference rate reform related activities that impact debt, leases, derivatives and other contracts. The guidance is optional and is effective between March 12, 2020 and December 31, 2024, which was extended from the original sunset date of December 31, 2022 when the FASB issued ASU No. 2022-06 in December 2022. The guidance may be elected over time as reference rate reform activities occur. During the first quarter of 2020, the Company elected to apply the hedge accounting expedients related to probability and the assessments of effectiveness for future LIBOR-indexed cash flows to assume that the index upon which future hedged transactions will be based matches the index on the corresponding derivatives. Application of these expedients preserves the presentation of derivatives consistent with past presentation. The impact of this guidance did not have a material impact on the Company's consolidated financial statements.
Fair Value Measurements	Fair Value Measurements We are required to disclose fair value information with regard to certain of our financial instruments, whether or not recognized in the consolidated balance sheets, for which it is practical to estimate fair value. The FASB guidance defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. We measure and/or disclose the estimated fair value of certain financial assets and liabilities based on a hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity and the reporting entity’s own assumptions about market participant assumptions. This hierarchy consists of three broad levels: Level 1 - quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity can access at the measurement date; Level 2 - inputs other than quoted prices included within Level 1, that are observable for the asset or liability, either directly or indirectly; and Level 3 - unobservable inputs for the asset or liability that are used when little or no market data is available. We follow this hierarchy for our assets and liabilities measured at fair value on a recurring and nonrecurring basis. In instances in which the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level of input that is significant to the fair value measurement in its entirety. Our assessment of the significance of the particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. We evaluate real estate investments and debt and preferred equity investments, including intangibles, for potential impairment primarily utilizing cash flow projections that apply, among other things, estimated revenue and expense growth rates, discount rates and capitalization rates, as well as sales comparison approach, which utilizes comparable sales, listings and sales contracts, all of which are classified as Level 3 inputs. In March 2024, the Company entered into an agreement to acquire its partner's 45.0% interest in the 10 East 53rd Street joint venture. As a result of the contract terms, it was concluded that the joint venture is a VIE in which the Company is the primary beneficiary, and the investment was consolidated in our financial statements. Upon consolidating the entity, the assets and liabilities of the entity were recorded at fair value which resulted in the recognition of a fair value adjustment of ($55.7 million), which is included in Purchase price and other fair value adjustments in the consolidated statements of operations. This fair value was determined using a third-party valuation which primarily utilized cash flow projections that apply, among other things, estimated revenue and expense growth rates, discount rates and capitalization rates, as well as the sales comparison approach, which utilizes comparable sales, listings, and sales contracts. All of which are classified as Level 3 inputs. Marketable securities classified as Level 1 are derived from quoted prices in active markets. The valuation technique used to measure the fair value of marketable securities classified as Level 2 were valued based on quoted market prices or model driven valuations using the significant inputs derived from or corroborated by observable market data. We do not intend to sell these securities and it is not more likely than not that we will be required to sell the investments before recovery of their amortized cost bases. The fair value of derivative instruments is based on current market data received from financial sources that trade such instruments and are based on prevailing market data and derived from third party proprietary models based on well-recognized financial principles and reasonable estimates about relevant future market conditions, which are classified as Level 2 inputs. The senior obligations of consolidated securitization vehicles represent CMBS that are not owned by the Company. A majority of these securities are either traded in the marketplace or are similar to other securities that are traded in the marketplace. As the valuation of these amounts are based upon quoted prices for similar instruments in active markets, we generally utilize third party pricing service providers to determine the fair value. The Company evaluates and assesses the third party pricing by referring to recent trades of similar securities, ratings, subordination levels, current market data and credit issues. The Company maximizes the use of observable inputs over unobservable inputs and uses the value of the senior obligations of consolidated securitization vehicles as an indicator of the fair value of the real estate loans held by consolidated securitization vehicles. Depending on the significance of the fair value inputs used in determining the fair value, these securities are classified in either Level 2 or Level 3 of the fair value hierarchy. As such, these investments may move between Level 2 and Level 3 of the fair value hierarchy if the significant fair value inputs used to price the CMBS become or cease to be observable. The fair value of our secured borrowing is determined by projecting future cash flows, which takes into consideration various factors including discount rate and exit capitalization rate, as well as related asset performance and local or macro real estate performance. The inputs used in determining the Company's secured borrowing are considered Level 3. The financial assets and liabilities that are not measured at fair value on our consolidated balance sheets include cash and cash equivalents, restricted cash, accounts receivable, accounts payable and accrued expenses, debt and preferred equity investments, mortgages and other loans payable and other secured and unsecured debt. The carrying amount of cash and cash equivalents, restricted cash, accounts receivable, and accounts payable and accrued expenses reported in our consolidated balance sheets approximates fair value due to the short-term nature of these instruments. The fair value of debt and preferred equity investments, which is classified as Level 3, is estimated by discounting the future cash flows using current interest rates at which similar loans with the same maturities would be made to borrowers with similar credit ratings. The fair value of borrowings, which is classified as Level 3, is estimated by discounting the contractual cash flows of each debt instrument to their present value using adjusted market interest rates, which is provided by a third-party specialist.

Investments in Unconsolidated Joint Ventures - Schedule of Mortgage Notes and Other Loans Payable Collateralized by the Respective Joint Venture Properties and Assignment of Leases (Details)	9 Months Ended
	Sep. 30, 2024 USD ($) extension	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Total fixed rate debt	$ 1,587,898,000	$ 1,387,386,000
Total floating rate debt	60,900,000	110,000,000
Joint venture
Debt Instrument [Line Items]
Total fixed rate debt	11,521,648,000	12,000,559,000
Total floating rate debt	2,216,727,000	2,902,780,000
Total fixed rate and floating rate debt	13,738,375,000	14,903,339,000
Deferred financing costs, net	(85,064,000)	(104,062,000)
Total joint venture mortgages and other loans payable, net	13,653,311,000	14,799,277,000
Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	6,053,120,000	6,053,808,000
Total floating rate debt	823,296,000	1,298,467,000
Total fixed rate and floating rate debt	6,876,416,000	7,352,275,000
Deferred financing costs, net	(47,397,000)	(54,865,000)
Total joint venture mortgages and other loans payable, net	$ 6,829,019,000	7,297,410,000
650 Fifth Avenue \| Wharton Properties \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	50.00%
Interest rate, fixed rate debt (as a percent)	5.45%
Interest rate, floating rate debt (as a percent)	2.25%
Total fixed rate debt	$ 65,000,000	65,000,000
Total floating rate debt	210,000,000	210,000,000
650 Fifth Avenue \| Wharton Properties \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	32,500,000	32,500,000
Total floating rate debt	$ 105,000,000	105,000,000
1515 Broadway \| Allianz Real Estate of America \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	56.87%
Interest rate, fixed rate debt (as a percent)	3.93%
Total fixed rate debt	$ 746,330,000	762,002,000
1515 Broadway \| Allianz Real Estate of America \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 424,431,000	433,344,000
115 Spring Street \| Private Investors \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	51.00%
Interest rate, fixed rate debt (as a percent)	5.50%
Total fixed rate debt	$ 65,550,000	65,550,000
115 Spring Street \| Private Investors \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 33,431,000	33,431,000
450 Park Avenue \| Korean Institutional Investor / Israeli Institutional Investor \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	25.10%
Interest rate, fixed rate debt (as a percent)	6.10%
Total fixed rate debt	$ 282,789,000	271,394,000
450 Park Avenue \| Korean Institutional Investor / Israeli Institutional Investor \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 70,980,000	68,120,000
11 Madison Avenue \| PGIM Real Estate \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	60.00%
Interest rate, fixed rate debt (as a percent)	3.84%
Total fixed rate debt	$ 1,400,000,000	1,400,000,000
11 Madison Avenue \| PGIM Real Estate \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	840,000,000	840,000,000
One Madison Avenue \| Joint venture \| Construction Loans
Debt Instrument [Line Items]
Maximum facility capacity	$ 1,250,000,000
Term	5 years
Number of extension options \| extension	1
Period of extension options	1 year
One Madison Avenue \| National Pension Service of Korea / Hines Interest LP / International Investor \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	25.50%
Interest rate, fixed rate debt (as a percent)	7.10%
Total fixed rate debt	$ 625,567,000	733,103,000
One Madison Avenue \| National Pension Service of Korea / Hines Interest LP / International Investor \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 159,520,000	186,941,000
One Madison Avenue \| Prudential Real Estate Investors \| Joint venture
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)	3.10%
Total floating rate debt	$ 267,143,000	0
One Madison Avenue \| Prudential Real Estate Investors \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total floating rate debt	$ 68,121,000	0
15 Beekman \| A fund managed by Meritz Alternative Investment Management \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	20.00%
Interest rate, fixed rate debt (as a percent)	5.99%
Interest rate, floating rate debt (as a percent)
Total fixed rate debt	$ 120,000,000	0
Total floating rate debt	0	124,137,000
15 Beekman \| A fund managed by Meritz Alternative Investment Management \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	24,000,000	0
Total floating rate debt	$ 0	24,827,000
800 Third Avenue \| Private Investors \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	60.52%
Interest rate, fixed rate debt (as a percent)	3.37%
Total fixed rate debt	$ 177,000,000	177,000,000
800 Third Avenue \| Private Investors \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 107,120,000	107,120,000
919 Third Avenue \| New York State Teacher's Retirement System \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	51.00%
Interest rate, fixed rate debt (as a percent)	6.11%
919 Third Avenue \| New York State Teacher's Retirement System \| Joint venture \| Mortgage loan
Debt Instrument [Line Items]
Total fixed rate debt	$ 500,000,000	500,000,000
919 Third Avenue \| New York State Teacher's Retirement System \| Joint venture \| Common Stock \| Mortgage loan
Debt Instrument [Line Items]
Total fixed rate debt	$ 255,000,000	255,000,000
280 Park Avenue \| Vornado Realty Trust \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	50.00%
Interest rate, fixed rate debt (as a percent)	5.84%
Interest rate, floating rate debt (as a percent)
Total fixed rate debt	$ 1,075,000,000	0
Total floating rate debt	0	1,200,000,000
280 Park Avenue \| Vornado Realty Trust \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	537,500,000	0
Total floating rate debt	$ 0	600,000,000
245 Park Avenue \| U.S. Affiliate of Mori Trust Co., Ltd \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	50.10%
Interest rate, fixed rate debt (as a percent)	4.30%
Total fixed rate debt	$ 1,768,000,000	1,768,000,000
245 Park Avenue \| U.S. Affiliate of Mori Trust Co., Ltd \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 885,768,000	885,768,000
Worldwide Plaza \| RXR Realty / New York REIT \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	24.95%
Interest rate, fixed rate debt (as a percent)	3.98%
Total fixed rate debt	$ 1,200,000,000	1,200,000,000
Worldwide Plaza \| RXR Realty / New York REIT \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 299,400,000	299,400,000
East 220 Street 42 \| A fund managed by Meritz Alternative Investment Management \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	51.00%
East 220 Street 42 \| National Pension Service of Korea / Hines Interest LP \| Joint venture
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	6.77%
Total fixed rate debt	$ 496,412,000	505,412,000
East 220 Street 42 \| National Pension Service of Korea / Hines Interest LP \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 253,170,000	257,760,000
One Vanderbilt Avenue \| National Pension Service of Korea / Hines Interest LP \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	71.01%
Interest rate, fixed rate debt (as a percent)	2.95%
Total fixed rate debt	$ 3,000,000,000	3,000,000,000
One Vanderbilt Avenue \| National Pension Service of Korea / Hines Interest LP \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 2,130,300,000	2,130,300,000
5 Times Square \| RXR Realty led investment group \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	31.55%
Interest rate, floating rate debt (as a percent)	4.71%
Total floating rate debt	$ 1,163,451,000	610,010,000
5 Times Square \| RXR Realty led investment group \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total floating rate debt	$ 367,069,000	192,458,000
5 Times Square \| National Pension Service of Korea / Hines Interest LP \| Joint venture
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)
Total fixed rate debt	$ 0	477,783,000
5 Times Square \| National Pension Service of Korea / Hines Interest LP \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 0	150,740,000
625 Madison Avenue \| Winthrop Capital Advisors \| Joint venture
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)
Total fixed rate debt	$ 0	199,987,000
625 Madison Avenue \| Winthrop Capital Advisors \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	0	180,848,000
10 East 53rd Street
Debt Instrument [Line Items]
Total fixed rate debt	$ 205,000,000	0
10 East 53rd Street \| Canadian Pension Plan Investment Board \| Joint venture
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)
Total fixed rate debt	$ 0	220,000,000
10 East 53rd Street \| Canadian Pension Plan Investment Board \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 0	121,000,000
717 Fifth Avenue \| Wharton Properties / Private Investor \| Joint venture
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)
Total fixed rate debt	$ 0	655,328,000
717 Fifth Avenue \| Wharton Properties / Private Investor \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt	$ 0	71,536,000
11 West 34th Street \| Private Investor / Wharton Properties \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	30.00%
Interest rate, floating rate debt (as a percent)	1.45%
Total floating rate debt	$ 23,000,000	23,000,000
11 West 34th Street \| Private Investor / Wharton Properties \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total floating rate debt	$ 6,900,000	6,900,000
1552 Broadway \| Wharton Properties \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	50.00%
Interest rate, floating rate debt (as a percent)	2.75%
Total floating rate debt	$ 193,133,000	193,133,000
1552 Broadway \| Wharton Properties \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total floating rate debt	$ 96,566,000	96,567,000
100 Park Avenue \| Prudential Real Estate Investors \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	49.90%
Interest rate, floating rate debt (as a percent)	2.36%
Total floating rate debt	$ 360,000,000	360,000,000
100 Park Avenue \| Prudential Real Estate Investors \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total floating rate debt	$ 179,640,000	179,640,000
2 Herald Square \| Israeli Institutional Investor \| Joint venture
Debt Instrument [Line Items]
Economic interest (as a percent)	95.00%
Interest rate, floating rate debt (as a percent)
Total floating rate debt	$ 0	182,500,000
2 Herald Square \| Israeli Institutional Investor \| Joint venture \| Common Stock
Debt Instrument [Line Items]
Total floating rate debt	$ 0	$ 93,075,000

Significant Accounting Policies - Schedule of Properties Contributed of Annualized Cash Rent (Details) - Annualized Rent	3 Months Ended	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2024 tenant
Customer Concentration
Concentration of Credit Risk
Number of tenants (tenants)		1
Maximum percentage of annualized rent for any one tenant not individually disclosed (percent) (more than)	5.00%	5.00%
Investment Property Concentration Risk \| One Vanderbilt Avenue
Concentration of Credit Risk
Percentage of concentration (percent)	17.20%
Investment Property Concentration Risk \| 11 Madison Avenue
Concentration of Credit Risk
Percentage of concentration (percent)	8.70%
Investment Property Concentration Risk \| 420 Lexington Ave
Concentration of Credit Risk
Percentage of concentration (percent)	7.00%
Investment Property Concentration Risk \| 1515 Broadway
Concentration of Credit Risk
Percentage of concentration (percent)	6.70%
Investment Property Concentration Risk \| 245 Park Avenue
Concentration of Credit Risk
Percentage of concentration (percent)	6.00%
Investment Property Concentration Risk \| 1185 Avenue of the Americas
Concentration of Credit Risk
Percentage of concentration (percent)	5.90%
Investment Property Concentration Risk \| 280 Park Avenue
Concentration of Credit Risk
Percentage of concentration (percent)	5.10%
Tenant 1 \| Customer Concentration
Concentration of Credit Risk
Percentage of concentration (percent)		5.50%

Corporate Indebtedness - Schedule of Consolidated Interest Expense, Excluding Capitalized Interest (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Interest expense
Interest expense before capitalized interest	$ 51,342	$ 52,877	$ 149,713	$ 183,652
Interest on financing leases	1,127	1,113	3,371	3,329
Capitalized interest	(9,492)	(25,483)	(41,226)	(77,916)
Amortization of discount on assumed debt	167	0	331	2,842
Interest income	(1,053)	(1,067)	(3,122)	(2,193)
Interest expense, net	$ 42,091	$ 27,440	$ 109,067	$ 109,714

- Definition

Amount of interest expense classified as operating and nonoperating. Includes, but is not limited to, cost of borrowing accounted for as interest expense.

+ References + Details

- Definition

Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1)(e))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 48
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-48

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14(Column E)(1))
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14(Column E)(Footnote 4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479168/946-830-55-10

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
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-Section 45
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
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-Paragraph 1
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-Publisher FASB
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Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 6
-Subparagraph (SX 210.12-14(Column E)(Footnote 6)(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6

+ Details

Mortgages and Other Loans Payable (Tables)

9 Months Ended

Sep. 30, 2024

Mortgages and Other Loans Payable

Schedule of Mortgages and Other Loans Payable

The mortgages and other loans payable collateralized by the respective properties and assignment of leases or debt investments as of September 30, 2024 and December 31, 2023, respectively, were as follows (dollars in thousands):


Property	Current Maturity Date	Final Maturity Date (1)	Interest Rate (2)		September 30, 2024		December 31, 2023
Fixed Rate Debt:
420 Lexington Avenue	October 2024 (3)	October 2040 (3)		3.99%	$	272,750	$	277,238
10 East 53rd Street	May 2025	May 2028		5.45%	205,000		—
100 Church Street	June 2025	June 2027		5.89%	370,000		370,000
7 Dey / 185 Broadway	November 2025	November 2026		6.65%	190,148		190,148
Landmark Square	January 2027	January 2027		4.90%	100,000		100,000
485 Lexington Avenue	February 2027	February 2027		4.25%	450,000		450,000
Total fixed rate debt					$	1,587,898	$	1,387,386
Floating Rate Debt:
690 Madison Avenue (4)	July 2025	July 2025	S+	0.50%	$	60,900	$	60,000
719 Seventh Avenue					—		50,000
Total floating rate debt					$	60,900	$	110,000


Total mortgages and other loans payable					$	1,648,798	$	1,497,386
Deferred financing costs, net of amortization					(4,806)		(6,067)
Total mortgages and other loans payable, net					$	1,643,992	$	1,491,319

(1)Reflects exercise of all available extension options. The ability to exercise extension options may be subject to certain conditions, including the operating performance of the property.

(2)Interest rate as of September 30, 2024, taking into account interest rate hedges in effect during the period. Floating rate debt is presented with the stated spread over Term SOFR ("S"), unless otherwise specified.

(3)In October 2024, the loan was extended through October 2040.

(4)Included in the Company's alternative strategy portfolio.

Stockholders' Equity of the Company - Earnings per Share (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Basic Earnings:
Loss attributable to SL Green common stockholders	$ (13,279)	$ (23,967)	$ (2,298)	$ (423,892)
Less: distributed earnings allocated to participating securities	(435)	(408)	(1,309)	(1,225)
Net loss attributable to SLGOP common unitholders (numerator for basic earnings per unit)	(13,714)	(24,375)	(3,607)	(425,117)
Effect of Dilutive Securities:
Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares	0	0	0	0
Add back: effect of dilutive securities (redemption of units to common shares)	0	(1,574)	0	(27,493)
Diluted Earnings:
Net loss attributable to SL Green common stockholders (numerator for diluted earnings per share)	$ (13,714)	$ (25,949)	$ (3,607)	$ (452,610)
Basic Shares:
Weighted average common shares outstanding (shares)	64,388,000	64,114,000	64,355,000	64,099,000
Effect of Dilutive Securities:
Operating Partnership units redeemable for common shares (shares)	0	4,182,000	0	4,175,000
Diluted weighted average common stock outstanding (shares)	64,388,000	68,296,000	64,355,000	68,274,000
Common stock shares excluded from the diluted shares outstanding (shares)	5,345,430	1,402,771	5,155,662	1,380,364

Consolidated Statements of Operations (Partnership) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Expenses
Operating expenses	$ 49,507	$ 49,585	$ 139,448	$ 148,606
Related party
Expenses
Operating expenses	0	2	2	3
SL Green Operating Partnership
Expenses
Operating expenses	49,507	49,585	139,448	148,606
SL Green Operating Partnership \| Related party
Expenses
Operating expenses	$ 0	$ 2	$ 2	$ 3

Share-based Compensation - Stock Options and Restricted Stock Activity (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares
Stock Options
Options Outstanding
Balance at beginning of period (in shares)	115,980	313,480
Exercised (in shares)	0	0
Lapsed or canceled (in shares)	0	(197,500)
Balance at end of period (in shares)	115,980	115,980
Options exercisable at end of period (in shares)	115,980	115,980
Weighted Average Exercise Price
Balance at beginning of year (in dollars per share) \| $ / shares	$ 103.52	$ 97.59
Exercised (in dollars per share) \| $ / shares	0	0
Lapsed or canceled (in dollars per share) \| $ / shares	0	84.14
Balance at end of period (in dollars per share) \| $ / shares	103.52	103.52
Options exercisable at end of period (in dollars per share) \| $ / shares	$ 103.52	$ 103.52
Restricted Stock Awards
Summary of restricted stock
Balance at beginning of year (in shares)	4,089,174	3,758,174
Granted (in shares)	7,734	337,350
Canceled (in shares)	(10,050)	(6,350)
Balance at end of period (in shares)	4,086,858	4,089,174
Vested during the period (in shares)	136,120	147,915
Compensation expense \| $	$ 7,935,369	$ 7,766,055
Total fair value of shares granted during the period \| $	$ 394,851	$ 15,789,540

Mortgages and Other Loans Payable - Narrative (Details) - USD ($) $ in Billions	Sep. 30, 2024	Dec. 31, 2023
Mortgages and Other Loans Payable
Book value of collateral	$ 1.8	$ 1.9

Mortgages and Other Loans Payable - Schedule of Mortgages and Other Loans Payable (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Total fixed rate debt	$ 1,587,898	$ 1,387,386
Total floating rate debt	60,900	110,000
Total mortgages and other loans payable	1,648,798	1,497,386
Deferred financing costs, net of amortization	(4,806)	(6,067)
Total mortgages and other loans payable, net	1,643,992	1,491,319
420 Lexington Ave
Debt Instrument [Line Items]
Total fixed rate debt	272,750	277,238
10 East 53rd Street
Debt Instrument [Line Items]
Total fixed rate debt	205,000	0
100 Church Street
Debt Instrument [Line Items]
Total fixed rate debt	370,000	370,000
7 Dey / 185 Broadway
Debt Instrument [Line Items]
Total fixed rate debt	190,148	190,148
Landmark Square
Debt Instrument [Line Items]
Total fixed rate debt	100,000	100,000
485 Lexington Avenue
Debt Instrument [Line Items]
Total fixed rate debt	450,000	450,000
690 Madison Avenue
Debt Instrument [Line Items]
Total floating rate debt	60,900	60,000
719 Seventh Avenue
Debt Instrument [Line Items]
Total floating rate debt	$ 0	$ 50,000
Weighted Average \| 420 Lexington Ave
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	3.99%
Weighted Average \| 10 East 53rd Street
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	5.45%
Weighted Average \| 100 Church Street
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	5.89%
Weighted Average \| 7 Dey / 185 Broadway
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	6.65%
Weighted Average \| Landmark Square
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.90%
Weighted Average \| 485 Lexington Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.25%
Weighted Average \| 690 Madison Avenue
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)	0.50%
Weighted Average \| 719 Seventh Avenue
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)

Share-based Compensation (Tables)

9 Months Ended

Sep. 30, 2024

Share-Based Payment Arrangement [Abstract]

Schedule of the Status of Stock Options and Changes During the Period


	September 30, 2024			December 31, 2023
	Options Outstanding	Weighted Average Exercise Price		Options Outstanding	Weighted Average Exercise Price
Balance at beginning of period	115,980	$	103.52	313,480	$	97.59

Exercised	—	—		—	—
Lapsed or canceled	—	—		(197,500)	84.14
Balance at end of period	115,980	$	103.52	115,980	$	103.52
Options exercisable at end of period	115,980	$	103.52	115,980	$	103.52

Schedule of Other Share-based Compensation, Activity


	September 30, 2024		December 31, 2023
Balance at beginning of period	4,089,174		3,758,174
Granted	7,734		337,350
Canceled	(10,050)		(6,350)
Balance at end of period	4,086,858		4,089,174
Vested during the period	136,120		147,915
Compensation expense recorded	$	7,935,369	$	7,766,055
Total fair value of restricted stock granted during the period	$	394,851	$	15,789,540

Organization and Basis of Presentation - Additional Information (Details) ft² in Millions, $ in Millions	9 Months Ended
	Sep. 30, 2024 USD ($) ft² building shares	Dec. 31, 2023
Organization
Debt and preferred equity investments including investments held by unconsolidated joint ventures \| $	$ 293.9
Debt and preferred equity investments and other financing receivables included in other balance sheet items \| $	$ 9.3
Number of shares to be received on redemption of one unit of limited partnership interests (shares) \| shares	1
Managed Office Properties
Organization
Number of buildings \| building	1
Unaudited Approximate Usable Square Feet \| ft²	0.4
Retail Site
Organization
Number of buildings \| building	1
Service Corporation
Organization
Percentage of ownership in SL Green Management LLC owned by operating partnership (percent)	95.00%
Operating Partnership \| SL Green Operating Partnership
Organization
Noncontrolling interest in the operating partnership (as a percent)	6.42%	5.75%
SL Green Management \| SL Green Management LLC
Organization
Percentage of ownership in SL Green Management LLC owned by operating partnership (percent)	100.00%

Stockholders' Equity of the Company - Schedule of Common Stock Issued and Proceeds Received Dividend Reinvestments (Details) - Dividend Reinvestment and Stock Purchase Plan (DRIP) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Stockholders' Equity
Shares of common stock issued (in shares)	338,704	2,695	341,180	14,736
Dividend reinvestments/stock purchases under the DRSPP	$ 23,633	$ 97	$ 23,754	$ 439

Corporate Indebtedness

9 Months Ended

Sep. 30, 2024

Debt Disclosure [Abstract]

Corporate Indebtedness

Mortgages and Other Loans Payable


Property	Current Maturity Date	Final Maturity Date (1)	Interest Rate (2)		September 30, 2024		December 31, 2023
Fixed Rate Debt:
420 Lexington Avenue	October 2024 (3)	October 2040 (3)		3.99%	$	272,750	$	277,238
10 East 53rd Street	May 2025	May 2028		5.45%	205,000		—
100 Church Street	June 2025	June 2027		5.89%	370,000		370,000
7 Dey / 185 Broadway	November 2025	November 2026		6.65%	190,148		190,148
Landmark Square	January 2027	January 2027		4.90%	100,000		100,000
485 Lexington Avenue	February 2027	February 2027		4.25%	450,000		450,000
Total fixed rate debt					$	1,587,898	$	1,387,386
Floating Rate Debt:
690 Madison Avenue (4)	July 2025	July 2025	S+	0.50%	$	60,900	$	60,000
719 Seventh Avenue					—		50,000
Total floating rate debt					$	60,900	$	110,000


Total mortgages and other loans payable					$	1,648,798	$	1,497,386
Deferred financing costs, net of amortization					(4,806)		(6,067)
Total mortgages and other loans payable, net					$	1,643,992	$	1,491,319

(1)Reflects exercise of all available extension options. The ability to exercise extension options may be subject to certain conditions, including the operating performance of the property.

(3)In October 2024, the loan was extended through October 2040.

(4)Included in the Company's alternative strategy portfolio.

As of September 30, 2024 and December 31, 2023, the gross book value of the properties collateralizing the mortgages and other loans payable was approximately $1.8 billion and $1.9 billion, respectively.

Corporate Indebtedness

2021 Credit Facility

In December 2021, we entered into an amended and restated credit facility, referred to as the 2021 credit facility, that was previously amended by the Company in November 2017, and was originally entered into by the Company in November 2012. As of September 30, 2024, the 2021 credit facility consisted of a $1.25 billion revolving credit facility, a $1.05 billion term loan (or "Term Loan A"), and a $200.0 million term loan (or "Term Loan B") with maturity dates of May 15, 2026, May 15, 2027, and November 21, 2024, respectively. The revolving credit facility has two six-month, as-of-right extension options to May 15, 2027. We also have an option, subject to customary conditions, to increase the capacity of the credit facility to $4.5 billion at any time prior to the maturity dates for the revolving credit facility and term loans without the consent of existing lenders, by obtaining additional commitments from our existing lenders and other financial institutions.

As of September 30, 2024, the 2021 credit facility bore interest at a spread over adjusted Term SOFR plus 10 basis points with an interest period of one or three months, as we may elect, ranging from (i) 72.5 basis points to 140 basis points for loans under the revolving credit facility, (ii) 80 basis points to 160 basis points for loans under Term Loan A, and (iii) 85 basis points to 165 basis points for loans under Term Loan B, in each case based on the credit rating assigned to the senior unsecured long term indebtedness of the Company. In instances where there are either only two ratings available or where there are more than two and the difference between them is one rating category, the applicable rating shall be the highest rating. In instances where there are more than two ratings and the difference between the highest and the lowest is two or more rating categories, then the applicable rating used is the average of the highest two, rounded down if the average is not a recognized category.

As of September 30, 2024, the applicable spread over adjusted Term SOFR plus 10 basis points for the 2021 credit facility was 140 basis points for the revolving credit facility, 160 basis points for Term Loan A, and 165 basis points for Term Loan B. We are required to pay quarterly in arrears a 12.5 to 30 basis point facility fee on the total commitments under the revolving credit facility based on the credit rating assigned to the senior unsecured long term indebtedness of the Company. As of September 30, 2024, the facility fee was 30 basis points.

As of September 30, 2024, we had $7.5 million of outstanding letters of credit, $735.0 million drawn under the revolving credit facility and $1.25 billion of outstanding term loans, with total undrawn capacity of $507.5 million under the 2021 credit facility. As of September 30, 2024 and December 31, 2023, the revolving credit facility had a carrying value of $730.9 million and $554.8 million, respectively, net of deferred financing costs. As of September 30, 2024 and December 31, 2023, the term loans had a carrying value of $1.2 billion and $1.2 billion, respectively, net of deferred financing costs.

The Company and the Operating Partnership are borrowers jointly and severally obligated under the 2021 credit facility.

The 2021 credit facility includes certain restrictions and covenants (see Restrictive Covenants below).

Senior Unsecured Notes


Issuance	September 30, 2024 Unpaid Principal Balance		September 30, 2024 Accreted Balance		December 31, 2023 Accreted Balance		Interest Rate (1)			Initial Term (in Years)	Maturity Date
December 17, 2015 (2)	$	100,000	$	100,000	$	100,000		4.27	%	10	December 2025


	$	100,000	$	100,000	$	100,000
Deferred financing costs, net	—		(128)		(205)
	$	100,000	$	99,872	$	99,795

(1)Interest rate as of September 30, 2024.

(2)Issued by the Company and the Operating Partnership as co-obligors in a private placement.

Restrictive Covenants

The terms of the 2021 credit facility and our senior unsecured notes include certain restrictions and covenants which may limit, among other things, our ability to pay dividends, make certain types of investments, incur additional indebtedness, incur liens and enter into negative pledge agreements and dispose of assets, and which require compliance with financial ratios relating to the maximum ratio of total indebtedness to total asset value, a minimum ratio of EBITDA to fixed charges, a maximum ratio of secured indebtedness to total asset value and a maximum ratio of unsecured indebtedness to unencumbered asset value. The dividend restriction referred to above provides that we will not, during any time when a default is continuing, make distributions with respect to common stock or other equity interests, except to enable the Company to continue to qualify as a REIT for Federal income tax purposes. As of September 30, 2024 and December 31, 2023, we were in compliance with all such covenants.

Junior Subordinated Deferrable Interest Debentures

In June 2005, the Company and the Operating Partnership issued $100.0 million in unsecured trust preferred securities through a newly formed trust, SL Green Capital Trust I, or the Trust, which is a wholly-owned subsidiary of the Operating Partnership. The securities mature in 2035 and bear interest at a floating rate of 26 basis points over the three-month Term SOFR. Interest payments may be deferred for a period of up to eight consecutive quarters if the Operating Partnership exercises its right to defer such payments. The Trust preferred securities are redeemable at the option of the Operating Partnership, in whole or in part, with no prepayment premium. We do not consolidate the Trust even though it is a variable interest entity as we are not the primary beneficiary. Because the Trust is not consolidated, we have recorded the debt on our consolidated balance sheets and the related payments are classified as interest expense.

Principal Maturities


	Scheduled Amortization		Principal		Revolving Credit Facility		Unsecured Term Loans		Trust Preferred Securities		Senior Unsecured Notes		Total		Joint Venture Debt
Remaining 2024	$	—	$	272,750	$	—	$	200,000	$	—	$	—	$	472,750	$	473,597
2025	—		430,900		—		—		—		100,000		530,900		1,910,561
2026	—		190,148		—		—		—		—		190,148		923,620
2027	—		550,000		735,000		1,050,000		—		—		2,335,000		1,438,338
2028	—		205,000		—		—		—		—		205,000		—
Thereafter	—		—		—		—		100,000		—		100,000		2,130,300
	$	—	$	1,648,798	$	735,000	$	1,250,000	$	100,000	$	100,000	$	3,833,798	$	6,876,416

Consolidated interest expense, excluding capitalized interest, was comprised of the following (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Interest expense before capitalized interest	$	51,342	$	52,877	$	149,713	$	183,652
Interest on financing leases	1,127		1,113		3,371		3,329
Capitalized interest	(9,492)		(25,483)		(41,226)		(77,916)
Amortization of discount on assumed debt	167		—		331		2,842
Interest income	(1,053)		(1,067)		(3,122)		(2,193)
Interest expense, net	$	42,091	$	27,440	$	109,067	$	109,714

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/470/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

+ Details

Organization and Basis of Presentation (Tables)

9 Months Ended

Sep. 30, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Commercial Office Properties


		Consolidated			Unconsolidated		Total
Location	Property Type	Number of Buildings		Approximate Square Feet (unaudited)	Number of Buildings	Approximate Square Feet (unaudited)	Number of Buildings	Approximate Square Feet (unaudited)	Weighted Average Leased Occupancy (1) (unaudited)
Commercial:
Manhattan	Office	14		8,753,441	10	13,009,149	24	21,762,590	89.9	%
	Retail	1		22,648	1	12,946	2	35,594	100.0	%
	Development/Redevelopment	2	(2)	880,771	1	1,385,484	3	2,266,255	N/A

		17		9,656,860	12	14,407,579	29	24,064,439	89.9	%
Suburban	Office	7		862,800	—	—	7	862,800	73.6	%



Total commercial properties		24		10,519,660	12	14,407,579	36	24,927,239	89.3	%
Residential:
Manhattan	Residential	1	(2)	140,382	1	221,884	2	362,266	99.0	%

Total core portfolio		25		10,660,042	13	14,629,463	38	25,289,505	89.4	%

	Alternative Strategy Portfolio (3)	1		7,848	8	3,694,956	9	3,702,804	49.4	%

(3)Represents non-core assets.

Related Party Transactions (Details) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 31, 2024	Apr. 30, 2024	Dec. 31, 2016	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2023
Related Party Transactions
Operating lease rent				$ 6,363	$ 7,253	$ 19,136	$ 20,209
Rental revenue, net				156,933	150,991	449,069	531,978
Related party receivables				13,077		13,077			$ 12,168
Joint venture
Related Party Transactions
Operating lease rent				8,487	7,307	25,990	21,746
Related party receivables				7,276		7,276			10,603
Other Affiliates
Related Party Transactions
Related party receivables				5,801		5,801			1,565
Related party
Related Party Transactions
Related party receivables				13,077		13,077			$ 12,168
One Vanderbilt Avenue
Related Party Transactions
Operating lease rent				700	700	2,200	2,200
SUMMIT One Vanderbilt
Related Party Transactions
Operating lease rent				20,800	17,000	33,400	31,100
Rental revenue, net				$ 14,400	$ 11,700	$ 22,700	$ 21,000
Holliday \| 760 Madison Avenue
Related Party Transactions
Proceeds from sale of property	$ 8,400
Holliday \| Payment of Interest Acquired \| One Vanderbilt Avenue
Related Party Transactions
Stabilization of property, liquidation value, amount monetized			$ 1,400
Mathias \| 719 Seventh Avenue \| Related party
Related Party Transactions
Proceeds from sale of property		$ 30,500
Expected equity ownership percentage		40.00%
Equity interest held by partner		$ 7,000
Mathias \| Payment of Interest Acquired \| One Vanderbilt Avenue
Related Party Transactions
Stabilization of property, liquidation value, amount monetized			$ 1,000
Holiday And Mathias \| One Vanderbilt Avenue
Related Party Transactions
Stabilization of property, within three years after stabilization, percent								50.00%
Stabilization period						3 years
Stabilization of property, three years or more after stabilization, percent						100.00%
Stabilization of property, anniversary period						7 years
Minimum \| Holliday \| One Vanderbilt Avenue
Related Party Transactions
Percentage of profits due to investors (as a percentage)			1.27%
Minimum \| Mathias \| One Vanderbilt Avenue
Related Party Transactions
Percentage of profits due to investors (as a percentage)			1.92%
Maximum \| Holliday \| One Vanderbilt Avenue
Related Party Transactions
Percentage of profits due to investors (as a percentage)			0.85%
Maximum \| Mathias \| One Vanderbilt Avenue
Related Party Transactions
Percentage of profits due to investors (as a percentage)			1.28%

- Details

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- Details

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Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2024

Accounting Policies [Abstract]

Schedule of Identified Intangible Assets and Intangible Liabilities

The following summarizes our identified intangible assets (acquired above-market leases and in-place leases) and intangible liabilities (acquired below-market leases) as of September 30, 2024 and December 31, 2023 (in thousands):


	September 30, 2024		December 31, 2023
Identified intangible assets (included in other assets):
Gross amount	$	273,010	$	189,680
Accumulated amortization	(193,327)		(184,902)
Net	$	79,683	$	4,778
Identified intangible liabilities (included in deferred revenue):
Gross amount	$	226,034	$	205,394
Accumulated amortization	(203,459)		(202,089)
Net	$	22,575	$	3,305

Schedule of Marketable Securities

As of September 30, 2024 and December 31, 2023, we held the following marketable securities (in thousands):


	September 30, 2024		December 31, 2023
Commercial mortgage-backed securities	$	16,522	$	9,591



Total investment in marketable securities	$	16,522	$	9,591

Schedule of Properties Contributed of Annualized Cash Rent

For the three months ended September 30, 2024, the following properties contributed more than 5.0% of our annualized cash rent from office properties, including our share of annualized cash rent from joint venture office properties:


Property			Three months ended September 30, 2024
One Vanderbilt Avenue			17.2%
11 Madison Avenue			8.7%
420 Lexington Ave			7.0%
1515 Broadway			6.7%
245 Park Avenue			6.0%
1185 Avenue of the Americas			5.9%
280 Park Avenue			5.1%

Schedule of Real Estate CMBS Securitization Trusts

As of September 30, 2024 and December 31, 2023, we consolidated the following CMBS securitization trusts (in thousands):


	September 30, 2024					December 31, 2023					Maturity
Type	Fair Value (1)			Principal Value			Fair Value		Principal Value


Real estate loans held by consolidated securitization vehicles	$	713,218	(2)	$	894,000		$	—	$	—		2023 - 2024	(3)
Senior obligations of consolidated securitization vehicles	603,902		(4)	703,675			—		—			2023 - 2024	(3)
Real estate loans held by consolidated securitization vehicles in excess of senior obligations of consolidated securitization vehicles	$	109,316		$	190,325		$	—	$	—

(1)Includes $126.4 million and $32.2 million of assets and liabilities, respectively, for a loan that is on non-accrual and is accounted for on an amortized cost basis.

(2)Includes $3.4 million of accrued interest income.

(3)The Company is in discussions with the respective borrowers on the resolution of the past maturities.

(4)Includes $2.3 million of accrued interest expense.

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Partners' Capital of the Operating Partnership - Additional Information (Details) - shares	9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Common Stock
Stockholders' Equity
Units outstanding (units)	65,235,000	64,814,000	64,726,000	64,398,000	64,387,000	64,380,000
SL Green Operating Partnership
Stockholders' Equity
Number of units of operating partnership owned by the noncontrolling interest unit holders (units)	4,474,406		3,949,448
SL Green Operating Partnership \| Operating Partnership
Stockholders' Equity
Noncontrolling interest in the operating partnership (as a percent)	6.42%		5.75%
SL Green Operating Partnership \| Common Stock
Stockholders' Equity
Shares, issued (in shares)	65,235,013
Units outstanding (units)	65,235,013
SL Green Operating Partnership \| Series I Preferred Units
Stockholders' Equity
Units outstanding (units)	9,200,000
Period of restriction to redeem OP Units	1 year
Conversion of stock, shares issued	1

Consolidated Statements of Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Stockholders' Equity [Abstract]
Cash distributions declared (per common unit, none of which represented a return of capital for federal income tax purposes) (in dollars per share)	$ 0.750	$ 0.812	$ 2.250	$ 2.437

Debt and Preferred Equity Investments - Schedule of Roll Forward of our Total Allowance for Loan Losses (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024 USD ($) loan	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) loan	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Loan loss reserve activity
Balance at beginning of year			$ 13,520	$ 6,630	$ 6,630
Current period provision for loan loss	$ 0	$ 0	0	$ 6,890	6,890
Balance at end of period	$ 13,520		$ 13,520		$ 13,520
Number of financing receivables on non-accrual without allowance for loan loss \| loan	1		1
Alternative Strategy Portfolio (3) \| Total floating rate
Loan loss reserve activity
Financing receivable on non-accrual without allowance	$ 49,800		$ 49,800

Significant Accounting Policies - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Investment in Marketable Securities
Marketable securities available-for-sale	$ 16,522	$ 9,591
Total investment in marketable securities	16,522	9,591
Commercial mortgage-backed securities
Investment in Marketable Securities
Marketable securities available-for-sale	$ 16,522	$ 9,591

Stockholders' Equity of the Company - At-the-Market Equity Offering Program and Perpetual Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	9 Months Ended
	Aug. 31, 2012	Sep. 30, 2024	Feb. 29, 2024	Dec. 31, 2023
Stockholders' Equity
Common stock, shares authorized (in shares)		160,000,000		160,000,000
Series I Preferred Stock
Stockholders' Equity
Preferred stock, shares outstanding (in shares)		9,200,000		9,200,000
Preferred stock, distribution rate		6.50%
Perpetual preferred stock, liquidation preference (in dollars per share)		$ 25.00		$ 25.00
Perpetual preferred stock, annual dividends per share (in dollars per share)		$ 1.625
Contributions of net proceeds from sale of preferred stock	$ 221.9
Dividend Reinvestment and Stock Purchase Plan (DRIP)
Stockholders' Equity
Common stock, shares authorized (in shares)			3,500,000

Debt and Preferred Equity Investments - Schedule of Debt Investments with an Aggregate Weighted Average Current Yield (Details) - USD ($)	1 Months Ended	9 Months Ended	21 Months Ended
	Jul. 31, 2023	Sep. 30, 2024	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2022
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate, interest rate		6.32%
Debt Investments Held [Abstract]
Carrying Value, Fixed Rate		$ 293,924,000	$ 293,924,000	$ 346,745,000
Carrying Value		293,924,000	293,924,000	346,745,000
Allowance for loan loss		(13,520,000)	(13,520,000)	(13,520,000)	$ (6,630,000)
Mezzanine Loan Due June 2024
Debt Investments Held [Abstract]
Amount participated out		12,000,000.0	12,000,000.0
Loan interest income	$ 0
Debt Investments in Mortgage Loans
Debt Investments Held [Abstract]
Future Funding Obligations		8,099,000	8,099,000
Senior Financing		804,021,000	804,021,000
Carrying Value		159,450,000	159,450,000	218,745,000
Allowance for loan loss		(13,520,000)	(13,520,000)	(13,520,000)
Total fixed rate
Debt Investments Held [Abstract]
Future Funding Obligations		0	0
Senior Financing		285,000,000	285,000,000
Carrying Value, Fixed Rate		63,366,000	63,366,000	63,366,000
Total fixed rate \| Mezzanine Loan Due June 2024
Debt Investments Held [Abstract]
Future Funding Obligations		0	0
Senior Financing		105,000,000	105,000,000
Carrying Value, Fixed Rate		13,366,000	13,366,000	13,366,000
Total fixed rate \| Mezzanine Loan, with an Initial Maturity Date of January 2025
Debt Investments Held [Abstract]
Future Funding Obligations		0	0
Senior Financing		95,000,000	95,000,000
Carrying Value, Fixed Rate		30,000,000	30,000,000	30,000,000
Total fixed rate \| Mezzanine Loan With Initial Maturity Date of December 2029
Debt Investments Held [Abstract]
Future Funding Obligations		0	0
Senior Financing		85,000,000	85,000,000
Carrying Value, Fixed Rate		20,000,000	20,000,000	20,000,000
Total floating rate
Debt Investments Held [Abstract]
Future Funding Obligations		8,099,000	8,099,000
Senior Financing		519,021,000	519,021,000
Carrying Value		109,604,000	109,604,000	168,899,000
Total floating rate \| Mezzanine Loan Due April 2023
Debt Investments Held [Abstract]
Future Funding Obligations		0	0
Senior Financing		275,000,000	275,000,000
Carrying Value		50,000,000	50,000,000	50,000,000
Loan interest income			0
Total floating rate \| Mezzanine Loan Due May 2024
Debt Investments Held [Abstract]
Future Funding Obligations		0	0
Senior Financing		54,000,000	54,000,000
Carrying Value		8,620,000	8,620,000	8,243,000
Total floating rate \| Mezzanine Loan Due May 2024 One
Debt Investments Held [Abstract]
Future Funding Obligations		8,099,000	8,099,000
Senior Financing		190,021,000	190,021,000
Carrying Value		50,984,000	50,984,000	48,323,000
Total floating rate \| Mezzanine Loan Due January 2026
Debt Investments Held [Abstract]
Future Funding Obligations		0	0
Senior Financing		0	0
Carrying Value		$ 0	$ 0	$ 62,333,000

Properties Held for Sale and Property Dispositions - Property sold (Details) $ in Millions	1 Months Ended
	Jul. 31, 2024 USD ($)	Jun. 30, 2024 USD ($) ft²	Sep. 30, 2024 USD ($)	Jul. 30, 2024 USD ($) ft²
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Employee-related liabilities			$ 7.8
719 Seventh Avenue
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Unaudited Approximate Usable Square Feet \| ft²		10,040
Sales price		$ 30.5
(Loss) gain on sale		$ (2.0)
Employee-related liabilities			$ 4.1
Palisades Premier Conference Center
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Unaudited Approximate Usable Square Feet \| ft²				450,000,000,000
Sales price				$ 26.3
(Loss) gain on sale	$ 7.3

Corporate Indebtedness - Schedule of Junior Subordinated Deferrable Interest Debentures and Principal Maturities (Details)	1 Months Ended
	Jun. 30, 2005 USD ($) quarter	Sep. 30, 2024 USD ($)
Principal Repayments and Joint Venture Debt
Remaining 2024		$ 472,750,000
2025		530,900,000
2026		190,148,000
2027		2,335,000,000
2028		205,000,000
Thereafter		100,000,000
Total principal repayments		3,833,798,000
Trust Preferred Securities
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 100,000,000.0
Interest rate added to base rate (as a percent)	0.26%
Interest payment deferment, number of consecutive quarters \| quarter	8
Joint venture
Principal Repayments and Joint Venture Debt
Remaining 2024		473,597,000
2025		1,910,561,000
2026		923,620,000
2027		1,438,338,000
2028		0
Thereafter		2,130,300,000
Total principal repayments		6,876,416,000
Joint venture \| Mortgages and other loans payable
Scheduled Amortization
Remaining 2024		0
2025		0
2026		0
2027		0
2028		0
Thereafter		0
Total amortization of debt		0
Principal Repayments and Joint Venture Debt
Remaining 2024		272,750,000
2025		430,900,000
2026		190,148,000
2027		550,000,000
2028		205,000,000
Thereafter		0
Total principal repayments		1,648,798,000
Joint venture \| Revolving Credit Facility
Principal Repayments and Joint Venture Debt
Remaining 2024		0
2025		0
2026		0
2027		735,000,000
2028		0
Thereafter		0
Total principal repayments		735,000,000
Joint venture \| Unsecured Term Loans
Principal Repayments and Joint Venture Debt
Remaining 2024		200,000,000
2025		0
2026		0
2027		1,050,000,000
2028		0
Thereafter		0
Total principal repayments		1,250,000,000
Joint venture \| Trust Preferred Securities
Principal Repayments and Joint Venture Debt
Remaining 2024		0
2025		0
2026		0
2027		0
2028		0
Thereafter		100,000,000
Total principal repayments		100,000,000
Joint venture \| Senior Unsecured Notes
Principal Repayments and Joint Venture Debt
Remaining 2024		0
2025		100,000,000
2026		0
2027		0
2028		0
Thereafter		0
Total principal repayments		$ 100,000,000

Corporate Indebtedness - Additional Information (Details)	9 Months Ended
	Sep. 30, 2024 USD ($) extension	Dec. 31, 2023 USD ($)
Corporate Indebtedness
Revolving credit facility, net	$ 730,851,000	$ 554,752,000
Term Loan A, Maturity May 2026 \| Term Loan
Corporate Indebtedness
Maximum facility capacity	$ 1,050,000,000.00
Interest rate added to base rate (as a percent)	1.60%
Term Loan A, Maturity May 2026 \| Minimum \| Term Loan
Corporate Indebtedness
Interest rate added to base rate (as a percent)	0.80%
Term Loan A, Maturity May 2026 \| Maximum \| Term Loan
Corporate Indebtedness
Interest rate added to base rate (as a percent)	1.60%
Term Loan B, Maturity November 2024 \| Term Loan
Corporate Indebtedness
Maximum facility capacity	$ 200,000,000.0
Interest rate added to base rate (as a percent)	1.65%
Term Loan B, Maturity November 2024 \| Minimum \| Term Loan
Corporate Indebtedness
Interest rate added to base rate (as a percent)	0.85%
Term Loan B, Maturity November 2024 \| Maximum \| Term Loan
Corporate Indebtedness
Interest rate added to base rate (as a percent)	1.65%
Revolving Credit Facility
Corporate Indebtedness
Facility fee (as a percent)	0.30%
Revolving credit facility, net	$ 735,000,000.0
Revolving Credit Facility \| Minimum
Corporate Indebtedness
Facility fee (as a percent)	0.125%
Revolving Credit Facility \| Maximum
Corporate Indebtedness
Facility fee (as a percent)	0.30%
Term Loan
Corporate Indebtedness
Long-term debt, carrying value	$ 1,250,000,000
Term Loan \| Line of Credit
Corporate Indebtedness
Long-term debt, carrying value	1,200,000,000	1,200,000,000
2012 Credit Facility
Corporate Indebtedness
Ability to borrow under line of credit facility	507,500,000
2012 Credit Facility \| Line of Credit
Corporate Indebtedness
Long-term debt, carrying value	730,900,000	$ 554,800,000
Revolving Credit Facility
Corporate Indebtedness
Letters of credit	$ 7,500,000
Revolving Credit Facility \| Line of Credit
Corporate Indebtedness
Interest rate added to base rate (as a percent)	0.10%
Revolving Credit Facility \| Revolving Credit Facility, Maturity May 2026 \| Line of Credit
Corporate Indebtedness
Maximum facility capacity	$ 1,250,000,000
Number of extensions \| extension	2
Term of extension	6 months
Maximum borrowing capacity, optional expansion	$ 4,500,000,000
Interest rate added to base rate (as a percent)	1.40%
Revolving Credit Facility \| Revolving Credit Facility, Maturity May 2026 \| Minimum \| Line of Credit
Corporate Indebtedness
Interest rate added to base rate (as a percent)	0.725%
Revolving Credit Facility \| Revolving Credit Facility, Maturity May 2026 \| Maximum \| Line of Credit
Corporate Indebtedness
Interest rate added to base rate (as a percent)	1.40%

Deferred Costs (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred leasing costs	$ 409,205	$ 399,224
Less: accumulated amortization	(303,559)	(287,761)
Deferred costs, net	$ 105,646	$ 111,463

Lease Income - Schedule of Lease Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Leases [Abstract]
Fixed lease payments	$ 140,450	$ 131,664	$ 405,130	$ 457,454
Variable lease payments	17,317	19,467	45,687	60,211
Total lease payments	157,767	151,131	450,817	517,665
Amortization of acquired above and below-market leases	(834)	(140)	(1,748)	14,313
Total rental revenue	156,933	150,991	449,069	531,978
Sublease Income	47,400	49,700	141,600	147,400
Interest income	$ 1,127	$ 1,113	$ 3,369	$ 3,328

Mortgages and Other Loans Payable

9 Months Ended

Sep. 30, 2024

Mortgages and Other Loans Payable

Mortgages and Other Loans Payable


Property	Current Maturity Date	Final Maturity Date (1)	Interest Rate (2)		September 30, 2024		December 31, 2023
Fixed Rate Debt:
420 Lexington Avenue	October 2024 (3)	October 2040 (3)		3.99%	$	272,750	$	277,238
10 East 53rd Street	May 2025	May 2028		5.45%	205,000		—
100 Church Street	June 2025	June 2027		5.89%	370,000		370,000
7 Dey / 185 Broadway	November 2025	November 2026		6.65%	190,148		190,148
Landmark Square	January 2027	January 2027		4.90%	100,000		100,000
485 Lexington Avenue	February 2027	February 2027		4.25%	450,000		450,000
Total fixed rate debt					$	1,587,898	$	1,387,386
Floating Rate Debt:
690 Madison Avenue (4)	July 2025	July 2025	S+	0.50%	$	60,900	$	60,000
719 Seventh Avenue					—		50,000
Total floating rate debt					$	60,900	$	110,000


Total mortgages and other loans payable					$	1,648,798	$	1,497,386
Deferred financing costs, net of amortization					(4,806)		(6,067)
Total mortgages and other loans payable, net					$	1,643,992	$	1,491,319

(1)Reflects exercise of all available extension options. The ability to exercise extension options may be subject to certain conditions, including the operating performance of the property.

(3)In October 2024, the loan was extended through October 2040.

(4)Included in the Company's alternative strategy portfolio.

Corporate Indebtedness

2021 Credit Facility

The Company and the Operating Partnership are borrowers jointly and severally obligated under the 2021 credit facility.

The 2021 credit facility includes certain restrictions and covenants (see Restrictive Covenants below).

Senior Unsecured Notes


Issuance	September 30, 2024 Unpaid Principal Balance		September 30, 2024 Accreted Balance		December 31, 2023 Accreted Balance		Interest Rate (1)			Initial Term (in Years)	Maturity Date
December 17, 2015 (2)	$	100,000	$	100,000	$	100,000		4.27	%	10	December 2025


	$	100,000	$	100,000	$	100,000
Deferred financing costs, net	—		(128)		(205)
	$	100,000	$	99,872	$	99,795

(1)Interest rate as of September 30, 2024.

(2)Issued by the Company and the Operating Partnership as co-obligors in a private placement.

Restrictive Covenants

Junior Subordinated Deferrable Interest Debentures

Principal Maturities


	Scheduled Amortization		Principal		Revolving Credit Facility		Unsecured Term Loans		Trust Preferred Securities		Senior Unsecured Notes		Total		Joint Venture Debt
Remaining 2024	$	—	$	272,750	$	—	$	200,000	$	—	$	—	$	472,750	$	473,597
2025	—		430,900		—		—		—		100,000		530,900		1,910,561
2026	—		190,148		—		—		—		—		190,148		923,620
2027	—		550,000		735,000		1,050,000		—		—		2,335,000		1,438,338
2028	—		205,000		—		—		—		—		205,000		—
Thereafter	—		—		—		—		100,000		—		100,000		2,130,300
	$	—	$	1,648,798	$	735,000	$	1,250,000	$	100,000	$	100,000	$	3,833,798	$	6,876,416

Consolidated interest expense, excluding capitalized interest, was comprised of the following (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Interest expense before capitalized interest	$	51,342	$	52,877	$	149,713	$	183,652
Interest on financing leases	1,127		1,113		3,371		3,329
Capitalized interest	(9,492)		(25,483)		(41,226)		(77,916)
Amortization of discount on assumed debt	167		—		331		2,842
Interest income	(1,053)		(1,067)		(3,122)		(2,193)
Interest expense, net	$	42,091	$	27,440	$	109,067	$	109,714

- Definition

+ References

+ Details

Debt and Preferred Equity Investments - Additional Information (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024 USD ($) investment	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) investment segment	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($) investment segment
Preferred equity investment
Number of investments, nonperforming \| investment	2		2		2
Debt and preferred equity investments	$ 293,924,000		$ 293,924,000		$ 346,745,000
Recorded investment, past due	293,924,000		$ 293,924,000		$ 346,745,000
Number of portfolio segments of financial receivables (segment) \| segment			1		1
Current period provision for loan loss	0	$ 0	$ 0	$ 6,890,000	$ 6,890,000
Other Assets
Preferred equity investment
Current period provision for loan loss			0	$ 0
Other Assets
Preferred equity investment
Additional amount of financing receivables included in other assets	10,900,000		10,900,000		8,800,000
Financing Receivables, Equal to Greater than 90 Days Past Due
Preferred equity investment
Recorded investment, past due	0		0		0
Three Mortgage Investments
Preferred equity investment
Debt and preferred equity investments	49,800,000		49,800,000
Floating Rate
Preferred equity investment
Debt and preferred equity investments	$ 109,604,000		$ 109,604,000		168,899,000
Floating Rate \| Mortgage Investment One
Preferred equity investment
Debt and preferred equity investments					$ 49,800,000

Investments in Unconsolidated Joint Ventures - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated joint ventures	$ 2,871,683		$ 2,871,683		$ 2,983,313
Net equity investment in VIEs in which the entity is not primary beneficiary	261,000		261,000		$ 437,900
Total revenues	229,691	$ 210,186	640,393	$ 701,986
Joint venture
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated joint ventures	2,871,683		2,871,683
Equity method investments with negative book value	179,100		179,100
Total revenues	376,949	407,148	1,107,295	1,140,889
Joint venture \| Base management service
Schedule of Equity Method Investments [Line Items]
Total revenues	$ 6,100	$ 3,500	$ 12,700	$ 16,300

- Definition

+ References + Details

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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+ Details

Significant Accounting Policies

9 Months Ended

Sep. 30, 2024

Accounting Policies [Abstract]

Significant Accounting Policies

Principles of Consolidation

The consolidated financial statements include our accounts and those of our subsidiaries, which are wholly-owned or controlled by us. Entities which we do not control through our voting interest, but have significant influence over, and entities which are variable interest entities, but where we are not the primary beneficiary, are accounted for under the equity method. See Note 5, "Debt and Preferred Equity Investments" and Note 6, "Investments in Unconsolidated Joint Ventures."

We consolidate a VIE in which we are considered the primary beneficiary. The primary beneficiary is the entity that has (i) the power to direct the activities that most significantly impact the entity's economic performance and (ii) the obligation to absorb losses of the VIE or the right to receive benefits from the VIE that could be significant to the VIE.

All significant intercompany balances and transactions have been eliminated.

Investment in Commercial Real Estate Properties

We allocate the purchase price of real estate to land and building (inclusive of tenant improvements) and, if determined to be material, intangibles, such as the value of above- and below-market leases and origination costs associated with the in-place leases. We depreciate the amount allocated to building (inclusive of tenant improvements) over their estimated useful lives, which generally range from 3 years to 40 years. We amortize the amount allocated to the above- and below-market leases over the remaining term of the associated lease, which generally range from 1 year to 15 years, and record it as either an increase (in the case of below-market leases) or a decrease (in the case of above-market leases) to rental income. We amortize the amount allocated to the values associated with in-place leases over the expected term of the associated lease, which generally ranges from 1 year to 15 years. If a tenant vacates its space prior to the contractual termination of the lease and no rental payments are being made on the lease, any unamortized balance of the related intangible will be written off. Origination costs are amortized as an expense over the remaining life of the lease and tenant improvements are amortized over the shorter of the remaining life of the lease or useful life of the improvement (or charged against earnings if the lease is terminated prior to its contractual expiration date). When allocating the purchase price of real estate, we assess fair value of the leases based on estimated cash flow projections that utilize appropriate discount rates and available market information. Estimates of future cash flows are based on a number of factors including the historical operating results, known trends, and market/economic conditions that may affect the property. To the extent acquired leases contain fixed rate renewal options that are below-market and determined to be material, we amortize such below-market lease value into rental income over the renewal period.

The Company classifies those leases under which the Company is the lessee at lease commencement as finance or operating leases. Leases qualify as finance leases if the lease transfers ownership of the asset at the end of the lease term, the lease grants an option to purchase the asset that we are reasonably certain to exercise, the lease term is for a major part of the remaining economic life of the asset, or the present value of the lease payments equals or exceeds substantially all of the fair value of the underlying asset. Leases that do not qualify as finance leases are deemed to be operating leases. At lease commencement the Company records a lease liability which is measured as the present value of the lease payments and a right of use asset which is measured as the amount of the lease liability and any initial direct costs incurred. The Company applies a discount rate to determine the present value of the lease payments. If the rate implicit in the lease is known, the Company uses that rate. If the rate implicit in the lease is not known, the Company uses a discount rate reflective of the Company’s collateralized borrowing rate given the term of the lease. To determine the discount rate, the Company employs a third-party specialist to develop an analysis based primarily on the observable borrowing rates of the Company, other REITs, and other corporate borrowers with long-term borrowings. On the consolidated statements of operations, operating leases are expensed through operating lease rent while financing leases are expensed through amortization and interest expense. When applicable, the Company combines the consideration for lease and non-lease components in the calculation of the value of the lease obligation and right-of-use asset.

On a quarterly basis, or when events or changes in circumstances arise, we assess whether there are any indications that the value of our real estate consolidated properties may be impaired or that their carrying value may not be recoverable. A consolidated property's value is considered impaired if management's estimate of the aggregate future cash flows (undiscounted) and terminal value to be generated by the property is less than the carrying value of the property. To the extent impairment has occurred, the loss will be measured as the excess of the carrying amount of the property over the fair value of the property as calculated in accordance with Accounting Standards Codification, or ASC 820. We also evaluate our real estate consolidated properties for impairment when a property has been classified as held for sale. Real estate assets held for sale are valued at the lower of their carrying value or fair value less costs to sell and depreciation expense is no longer recorded.

In April 2024, the Company entered into an agreement to sell the property at 719 Seventh Avenue for $30.5 million. As a result of the pending sale, the Company recorded a $46.3 million charge to reduce the carrying value of its investment to the contracted purchase price for the three months ended March 31, 2024, which is included in Depreciable real estate reserves and impairments in the consolidated statements of operations. The transaction closed during the second quarter of 2024. See Note 4, "Properties Held for Sale and Property Dispositions."

During the nine months ended September 30, 2024, the Company recorded a $13.7 million charge, reflective of $13.2 million of capitalized interest, to reduce the carrying value of the residential condominium units at 760 Madison Avenue, based on the total of the sales contracts that the Company entered into for these units. This charge is included in Depreciable real estate reserves and impairments in the consolidated statements of operations. The transactions are expected to close in the fourth quarter of 2024.

For the three and nine months ended September 30, 2024, we recognized a reduction of rental revenue of ($0.8 million) and ($1.7 million), respectively, for the amortization of aggregate above-market leases in excess of below-market leases resulting from the allocation of the purchase price of the applicable properties. For the three months ended September 30, 2023, we recognized a reduction in rental revenue of ($0.1 million) for the amortization of aggregate above-market leases in excess of below-market leases. For the nine months ended September 30, 2023, we recognized additional rental revenue of $14.3 million for the amortization of aggregate below-market leases in excess of above-market leases.


	September 30, 2024		December 31, 2023
Identified intangible assets (included in other assets):
Gross amount	$	273,010	$	189,680
Accumulated amortization	(193,327)		(184,902)
Net	$	79,683	$	4,778
Identified intangible liabilities (included in deferred revenue):
Gross amount	$	226,034	$	205,394
Accumulated amortization	(203,459)		(202,089)
Net	$	22,575	$	3,305

Cash and Cash Equivalents

We consider all highly liquid investments with maturity of three months or less when purchased to be cash equivalents.

Restricted Cash

Restricted cash primarily consists of security deposits held on behalf of our tenants, interest reserves, as well as capital improvement and real estate tax escrows required under certain loan agreements.

Fair Value Measurements

See Note 16, "Fair Value Measurements."

Investment in Marketable Securities

At acquisition, we designate a debt security as held-to-maturity, available-for-sale, or trading. As of September 30, 2024, we did not have any debt securities designated as held-to-maturity or trading. We account for our available-for-sale securities at fair value pursuant to ASC 820-10, with the net unrealized gains or losses reported as a component of accumulated other comprehensive income or loss. The cost of marketable securities sold and the amount reclassified out of accumulated other comprehensive income into earnings is determined using the specific identification method. Credit losses are recognized in accordance with ASC 326. We account for equity marketable securities at fair value pursuant to ASC 820-10, with the net unrealized gains or losses reported in net income.

As of September 30, 2024 and December 31, 2023, we held the following marketable securities (in thousands):


	September 30, 2024		December 31, 2023
Commercial mortgage-backed securities	$	16,522	$	9,591



Total investment in marketable securities	$	16,522	$	9,591

The cost basis of the commercial mortgage-backed securities ("CMBS") was $16.9 million and $11.5 million as of September 30, 2024 and December 31, 2023, respectively. These securities mature at various times through 2030. As of September 30, 2024, one security was in an unrealized gain position of $0.1 million with a fair market value of $5.4 million, and two securities were in an unrealized loss position of $0.9 million with a fair market value of $11.1 million with one of the securities being in a continuous unrealized loss position for more than 12 months. All securities were in an unrealized loss position as of December 31, 2023 with an unrealized loss of $1.9 million, a fair market value of $9.6 million and were in a continuous unrealized loss position for more than 12 months. We do not intend to sell our other securities, and it is more likely than not that we will not be required to sell the investments before recovery of their amortized cost bases.

We did not dispose of any debt marketable securities during the three and nine months ended September 30, 2024 and 2023.

We held no equity marketable securities as of September 30, 2024 and December 31, 2023.

Investment in CMBS Securitization Trusts

We may acquire securities in CMBS securitization trusts and, which in certain cases, we may be contracted to provide special servicing activities for these trusts. In certain cases, we may acquire the controlling class of the trust and we may have the right to name and remove the special servicer for these trusts. These circumstances may result in our consolidating the securitization trusts on our financial statements. We evaluate all of our positions and special servicer appointments for consolidation, which are considered to be VIEs to the Company.

As the special servicer, we provide services on defaulted loans within the trusts as permitted by the underlying contractual agreements. We receive a fee in exchange for these services. The rights provided to us as special servicer give us the ability to direct activities that could significantly impact the trust's economic performance, which requires consolidation of the securitization trust unless a third party has the right to unilaterally remove us as special servicer without cause. In such instances where we can be removed as special servicer without cause, we do not have the power to direct activities that most significantly impact the trust's economic performance and would not consolidate the securitization trust.

For CMBS securitization trusts in which we are determined to be the primary beneficiary, we consolidate the securitization trusts on our consolidated balance sheets. The consolidation of such securitization trusts results in a gross presentation of the underlying collateral loans as assets as well as the senior CMBS positions owned by third parties, which are presented as liabilities on our consolidated balance sheets. The assets of the consolidated securitization trust can only be used to satisfy the liabilities of that securitization and are not available to the Company for any other purpose. Additionally, the senior CMBS securitization trust obligations can only be satisfied through repayment of the underlying collateral loans as they do not have any recourse to the Company or our assets. The Company has not provided any guarantees with respect to the performance or repayment of the senior CMBS obligations.

While consolidation of the securitization trust increases the gross presentation of our consolidated balance sheets, it does not impact the economic exposure or performance of the Company as it is limited to that of the actual investment in the CMBS securitization trust, and not the consolidated senior obligations.

As of September 30, 2024 and December 31, 2023, we consolidated the following CMBS securitization trusts (in thousands):


	September 30, 2024					December 31, 2023					Maturity
Type	Fair Value (1)			Principal Value			Fair Value		Principal Value


Real estate loans held by consolidated securitization vehicles	$	713,218	(2)	$	894,000		$	—	$	—		2023 - 2024	(3)
Senior obligations of consolidated securitization vehicles	603,902		(4)	703,675			—		—			2023 - 2024	(3)
Real estate loans held by consolidated securitization vehicles in excess of senior obligations of consolidated securitization vehicles	$	109,316		$	190,325		$	—	$	—

(1)Includes $126.4 million and $32.2 million of assets and liabilities, respectively, for a loan that is on non-accrual and is accounted for on an amortized cost basis.

(2)Includes $3.4 million of accrued interest income.

(3)The Company is in discussions with the respective borrowers on the resolution of the past maturities.

(4)Includes $2.3 million of accrued interest expense.

We have elected to record the associated interest income and interest expense for these investments as separate line items on our consolidated statements of operations. The amounts recorded in Interest income from real estate loans held by consolidated securitization vehicles on our consolidated statements of operations include the Company's interest income as well as the interest income associated with CMBS positions owned by third parties, which is offset by the amounts recorded in Interest expense on senior obligations of consolidated securitization vehicles on our consolidated statements of operations. As a result, the net impact is limited to the interest income on the CMBS securities we own directly and not the gross consolidated interest income and interest expense.

Investments in Unconsolidated Joint Ventures

We assess our investments in unconsolidated joint ventures for recoverability and if it is determined that a loss in value of the investment is other than temporary, we write down the investment to its fair value. We evaluate our equity investments for impairment based on each joint ventures' actual and projected cash flows. Aside from charges noted in Note 6, "Investments in Unconsolidated Joint Ventures," we do not believe that the values of any of our equity investments were impaired at September 30, 2024.

Deferred Lease Costs

Deferred lease costs consist of incremental fees and direct costs that would not have been incurred if the lease had not been obtained and are amortized on a straight-line basis over the related lease term.

Lease Classification

Lease classification for leases under which the Company is the lessor is evaluated at lease commencement and leases not classified as sales-type leases or direct financing leases are classified as operating leases. Leases qualify as sales-type leases if the contract includes either transfer of ownership clauses, certain purchase options, a lease term representing a major part of the economic life of the asset, or the present value of the lease payments and residual guarantees provided by the lessee exceeds substantially all of the fair value of the asset. Additionally, leasing an asset so specialized that it is not deemed to have any value to the Company at the end of the lease term may also result in classification as a sales-type lease. Leases qualify as direct financing leases when the present value of the lease payments and residual value guarantees provided by the lessee and unrelated third parties exceeds substantially all of the fair value of the asset and collection of the payments is probable.

Revenue Recognition

Rental revenue for operating leases is recognized on a straight-line basis over the term of the lease. Rental revenue recognition commences when the leased space is available for its intended use by the lessee.

To determine whether the leased space is available for its intended use by the lessee, management evaluates whether we or the tenant are the owner of tenant improvements for accounting purposes. When management concludes that we are the owner of tenant improvements, rental revenue recognition begins when the tenant takes possession of the finished space, which is when such tenant improvements are substantially complete. In certain instances, when management concludes that we are not the owner of tenant improvements, rental revenue recognition begins when the tenant takes possession of or controls the space.

The excess of rents recognized over amounts contractually due pursuant to the underlying leases are included in deferred rents receivable on the consolidated balance sheets.

In addition to base rent, our tenants also generally will pay variable rent, which represents their pro rata share of increases in real estate taxes and certain operating expenses for the building over a base year. In some leases, in lieu of paying additional rent based upon increases in certain building operating expenses, the tenant will pay additional rent based upon increases in the wage rate paid to porters over the porters' wage rate in effect during a base year or increases in the consumer price index over the index value in effect during a base year. In addition, many of our leases contain fixed percentage increases over the base rent to cover escalations. Electricity is most often supplied by the landlord either on a sub-metered basis, or rent inclusion basis (i.e., a fixed fee is included in the rent for electricity, which amount may increase based upon increases in electricity rates or increases in electrical usage by the tenant). Base building services other than electricity (such as heat, air conditioning and freight elevator service during business hours, and base building cleaning) are typically provided at no additional cost, with the tenant paying additional rent only for services which exceed base building services or for services which are provided outside normal business hours. These escalations are based on actual expenses incurred in the prior calendar year. If the expenses in the current year are different from those in the prior year, then during the current year, the escalations will be adjusted to reflect the actual expenses for the current year.

Rental revenue is recognized if collectability is probable. If collectability of substantially all of the lease payments is assessed as not probable, any difference between the rental revenue recognized to date and the lease payments that have been collected is recognized as a current-period adjustment to rental revenue. A subsequent change in the assessment of collectability to probable may result in a current-period adjustment to rental revenue for any difference between the rental revenue that would have been recognized if collectability had always been assessed as probable and the rental revenue recognized to date.

The Company provides its tenants with certain customary services for lease contracts such as common area maintenance and general security. We have elected to combine the non-lease components with the lease components of our operating lease agreements and account for them as a single lease component in accordance with ASC 842.

We record a gain or loss on sale of real estate assets when we no longer have a controlling financial interest in the entity owning the real estate, a contract exists with a third party and that third party has control of the assets acquired.

Investment income on debt and preferred equity investments is accrued based on the contractual terms of the instruments and when it is deemed collectible. Some debt and preferred equity investments provide for accrual of interest at specified rates, which differ from current payment terms. Interest is recognized on such loans at the accrual rate subject to management's determination that accrued interest is collectible. If management cannot make this determination, interest income above the current pay rate is recognized only upon actual receipt.

Deferred origination fees, original issue discounts and loan origination costs, if any, are recognized as an adjustment to interest income over the terms of the related investments using the effective interest method. Fees received in connection with loan commitments are also deferred until the loan is funded and are then recognized over the term of the loan as an adjustment to yield. Discounts or premiums associated with the purchase of loans are amortized or accreted into interest income as a yield adjustment on the effective interest method based on expected cash flows through the expected maturity date of the related investment. If we purchase a debt or preferred equity investment at a discount, intend to hold it until maturity and expect to recover the full value of the investment, we accrete the discount into income as an adjustment to yield over the term of the investment. If we purchase a debt or preferred equity investment at a discount with the intention of foreclosing on the collateral, we do not accrete the discount. For debt investments acquired at a discount for credit quality, the difference between contractual cash flows and expected cash flows at acquisition is not accreted. Anticipated exit fees, the collection of which is expected, are also recognized over the term of the loan as an adjustment to yield.

We consider a debt and preferred equity investment to be past due when amounts contractually due have not been paid. Debt and preferred equity investments are placed on a non-accrual status at the earlier of the date at which payments become 90 days past due or when, in the opinion of management, a full recovery of interest income becomes doubtful. Interest income recognition is resumed on any debt or preferred equity investment that is on non-accrual status when such debt or preferred equity investment becomes contractually current and performance is demonstrated to be resumed.

We may syndicate a portion of the loans that we originate or sell the loans individually. When a transaction meets the criteria for sale accounting, we recognize gain or loss based on the difference between the sales price and the carrying value of the loan sold. Any related unamortized deferred origination fees, original issue discounts, loan origination costs, discounts or premiums at the time of sale are recognized as an adjustment to the gain or loss on sale, which is included in investment income on the consolidated statement of operations. Any fees received at the time of sale or syndication are recognized as part of investment income.

Asset management fees are recognized on a straight-line basis over the term of the asset management agreement.

Revenues from the sale of SUMMIT tickets are recognized upon admission or ticket expirations. Deferred revenue related to unused and unexpired tickets as of September 30, 2024 and December 31, 2023 was $3.8 million and $2.6 million, respectively, and is included in Deferred revenue on the consolidated balance sheets.

Debt and Preferred Equity Investments

Debt and preferred equity investments are presented at the net amount expected to be collected in accordance with ASC 326. An allowance for loan losses is deducted from the amortized cost basis of the financial assets to present the net carrying value at the amount expected to be collected through the expected maturity date of such investments. The expense for loan loss and other investment reserves is the charge to earnings to adjust the allowance for loan losses to the appropriate level. Amounts are written off from the allowance when we de-recognize the related investment either as a result of a sale of the investment or acquisition of equity interests in the collateral.

The Company evaluates the amount expected to be collected based on current market and economic conditions, historical loss information, and reasonable and supportable forecasts. The Company's assumptions are derived from both internal data and external data which may include, among others, governmental economic projections for the New York City Metropolitan area, public data on recent transactions and filings for securitized debt instruments. This information is aggregated by asset class and adjusted for duration. Based on these inputs, loans are evaluated at the individual asset level. In certain instances, we may also use a probability-weighted model that considers the likelihood of multiple outcomes and the amount expected to be collected for each outcome.

The evaluation of the possible credit deterioration associated with the performance and/or value of the underlying collateral property as well as the financial and operating capability of the borrower/sponsor requires significant judgment, which include both asset level and market assumptions over the relevant time period.

In addition, quarterly, the Company assigns each loan a risk rating. Based on a 3-point scale, loans are rated “1” through “3,” from lower risk to higher risk, which ratings are defined as follows: 1 - Low Risk Assets - Low probability of loss, 2 - Watch List Assets - Higher potential for loss, 3 - High Risk Assets - Loss more likely than not. Loans with risk ratings of 2 or above are evaluated to determine whether the expected risk of loss is appropriately captured through the combination of our expectations of current conditions, historical loss information and supportable forecasts described above or whether risk characteristics specific to the loan warrant the use of a probability-weighted model.

Financing investments that are classified as held for sale are carried at the expected amount to be collected or fair market value using available market information obtained through consultation with dealers or other originators of such investments as well as discounted cash flow models based on Level 3 data pursuant to ASC 820-10. As circumstances change, management may conclude not to sell an investment designated as held for sale. In such situations, the investment will be reclassified at its expected amount to be collected.

Other financing receivables that are included in balance sheet line items other than the Debt and preferred equity investments line are also measured at the net amount expected to be collected.

Accrued interest receivable amounts related to these debt and preferred equity investment and other financing receivables are recorded at the net amount expected to be collected within Other assets in the consolidated balance sheets. Accrued interest receivables that are written off are recognized as an expense in loan loss and other investment reserves.

Income Taxes

SL Green is taxed as a REIT under Section 856(c) of the Code. As a REIT, SL Green generally is not subject to Federal income tax. To maintain its qualification as a REIT, SL Green must distribute at least 90% of its REIT taxable income to its stockholders and meet certain other requirements. If SL Green fails to qualify as a REIT in any taxable year, SL Green will be subject to Federal income tax on its taxable income at regular corporate rates. SL Green may also be subject to certain state, local and franchise taxes. Under certain circumstances, Federal income and excise taxes may be due on its undistributed taxable income.

The Operating Partnership is a partnership and, as a result, all income and losses of the partnership are allocated to the partners for inclusion in their respective income tax returns. The only provision for income taxes included in the consolidated statements of operations relates to the Operating Partnership’s consolidated taxable REIT subsidiaries. The Operating Partnership may also be subject to certain state, local and franchise taxes.

We have elected, and may elect in the future, to treat certain of our corporate subsidiaries as taxable REIT subsidiaries, or TRSs. In general, TRSs may perform non-customary services for the tenants of the Company, hold assets that we cannot hold directly and generally may engage in any real estate or non-real estate related business. The TRSs generate income, resulting in Federal, state and local corporate tax liability for these entities. During the three and nine months ended September 30, 2024, we recorded Federal, state and local tax provisions totaling $1.1 million and $2.7 million, respectively, for these entities. During the three and nine months ended September 30, 2023, we recorded Federal, state and local tax provisions totaling $2.5 million and $5.2 million, respectively, for these entities.

SUMMIT is held in a TRS and pays Federal, state and local taxes. During the three and nine months ended September 30, 2024, we recorded Federal, state and local tax benefits for SUMMIT of $1.8 million and $1.2 million, respectively. During the three and nine months ended September 30, 2023, we recorded Federal, state and local tax expense for SUMMIT of $3.7 million and $6.9 million, respectively.

We follow a two-step approach for evaluating uncertain tax positions. Recognition (step one) occurs when an enterprise concludes that a tax position, based solely on its technical merits, is more-likely-than-not to be sustained upon examination. Measurement (step two) determines the amount of benefit that is more-likely-than-not to be realized upon settlement. Derecognition of a tax position that was previously recognized would occur when a company subsequently determines that a tax position no longer meets the more-likely-than-not threshold of being sustained. The use of a valuation allowance as a substitute for derecognition of tax positions is prohibited.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.

Concentrations of Credit Risk

Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash investments, debt and preferred equity investments and accounts receivable. We place our cash investments with high quality financial institutions. The collateral securing our debt and preferred equity investments is located in New York City. See Note 5, "Debt and Preferred Equity Investments."

We perform initial and ongoing evaluations of the credit quality of our tenants and require most tenants to provide security deposits or letters of credit. Though these security deposits and letters of credit are insufficient to meet the total value of a tenant's lease obligation, they are a measure of good faith and a potential source of funds to offset the economic costs associated with lost revenue from that tenant and the costs associated with re-tenanting a space. The properties in our real estate portfolio are located in the New York metropolitan area, principally in Manhattan. Our tenants operate in various industries. Other than one tenant, Paramount Global (formerly ViacomCBS Inc.), which accounted for 5.5% of our share of annualized cash rent as of September 30, 2024, no other tenant in our portfolio accounted for more than 5.0% of our share of annualized cash rent, including our share of joint venture annualized cash rent, for the three months ended September 30, 2024.


Property			Three months ended September 30, 2024
One Vanderbilt Avenue			17.2%
11 Madison Avenue			8.7%
420 Lexington Ave			7.0%
1515 Broadway			6.7%
245 Park Avenue			6.0%
1185 Avenue of the Americas			5.9%
280 Park Avenue			5.1%

Reclassification

Certain prior year balances have been reclassified to conform to our current year presentation.

Beginning in the second quarter of 2024, we reclassified amounts recorded for certain right-of-use assets classified as operating leases from a gross presentation above accumulated depreciation to a net presentation below accumulated depreciation in our consolidated balance sheets. This includes reclassifying the related amortization that was previously included in the accumulated depreciation. We believe this presentation enhances the Company's financial statements.

As of December 31, 2023, SUMMIT met the criteria of a reportable operating segment pursuant to the guidance in ASC 280. Accordingly, we reclassified SUMMIT Operator revenue, SUMMIT Operator expenses, and SUMMIT Operator tax expense to separate financial statement line items in our consolidated statements of operations. These items were previously presented on a net basis in Other income. Additionally, the depreciation and amortization of SUMMIT assets are included in Depreciation and amortization in our consolidated statements of operations. Prior period balances have been reclassified to conform to the current period presentation.

Accounting Standards Updates

In December 2023, the FASB issued ASU No. 2023-09 Income Taxes (Topic 740) - Improvements to Income Tax Disclosures. The objective of the amendments in ASU 2023-09 related to the rate reconciliation and income taxes paid disclosures are to improve transparency of income tax disclosures by requiring consistent categories and greater disaggregation of information in the rate reconciliation, and income taxes paid disaggregated by jurisdiction. The amendment will require that public entities on an annual basis disclose specific categories in the rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. Additionally, the amendment will require that all entities disclose on an annual basis the amount of taxes paid (net of refunds received) disaggregated by federal, state and foreign taxes as well as disaggregated by individual jurisdictions that meet a quantitative threshold. ASU 2023-09 is effective prospectively for annual periods beginning after December 15, 2024. Early adoption and retrospective application is permitted. We are currently evaluating the impact of the adoption of ASU 2023-09 on our consolidated financial statements, but do not believe the adoption of this standard will have a material impact on our consolidated financial statements.

In November 2023, the FASB issued ASU No. 2023-07 Segment Reporting (Topic 280) - Improvements to Reportable Segment Disclosures. ASU 2023-07 amends the reportable segment disclosure requirements to enhance disclosures about significant segment expenses. The objective of the amendment is to improve financial reporting by requiring disclosure of incremental segment information on an annual and interim basis for all public entities to enable investors to develop more decision-useful financial analyses. The amendment will require that a public entity disclose, on an annual and interim basis, significant segment expenses that are regularly provided to the chief operating decision maker ("CODM") and included within each reported measure of segment profit or loss (collectively referred to as the "significant expense principle"). Additionally, the amendment will require an entity to disclose an amount for "other segment items" by reportable segment and a description of its composition as well as require annual disclosures about a reportable segment's profit or loss and assets currently required by Topic 280 in interim periods. Lastly, the amendment will require a public entity to disclose the title and position of the CODM and an explanation of how the CODM uses the reported measures of segment profit or loss in assessing segment performance and deciding to allocate resources. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted and should be applied retrospectively to all prior periods presented in the financial statements. We are currently evaluating the impact of the adoption of ASU 2023-07 on our consolidated financial statements, but do not believe the adoption of this standard will have a material impact on our consolidated financial statements.

In August 2023, the FASB issued ASU No. 2023-05 Business Combinations - Joint Venture Formations (Subtopic 805-60) Recognition and Initial Measurement. ASU 2023-05 addresses the accounting for contributions made to a joint venture, upon formation, in a joint venture's separate financial statements. The objectives of the amendments are to provide decision-useful information to investors and other allocators of capital in a joint venture's financial statements and reduce diversity in practice. The amendments require that a joint venture apply the following key adaptations from the business combinations guidance upon formation: (i) a joint venture is the formation of a new entity without an accounting acquirer, (ii) a joint venture measures its identifiable net assets and goodwill, if any, at the formation date, (iii) initial measurement of a joint venture's total net assets is equal to the fair value of 100 percent of the joint venture's equity, and (iv) a joint venture provides relevant disclosures. ASU 2023-05 is effective prospectively for all joint venture formations with a formation date on or after January 1, 2025, with early adoption permitted in any interim or annual period in which financial statements have not yet been issued, either prospectively or retrospectively. We are currently evaluating the impact of the adoption of ASU 2023-05 on our consolidated financial statements, but do not believe the adoption of this standard will have a material impact on our consolidated financial statements.

In March 2020, the FASB issued ASU No. 2020-04 Reference Rate Reform (Topic 848) Facilitation of the Effects of Reference Rate Reform on Financial Reporting and then in January 2021, the FASB issued ASU No. 2021-01. The amendments provide practical expedients for reference rate reform related activities that impact debt, leases, derivatives and other contracts. The guidance is optional and is effective between March 12, 2020 and December 31, 2024, which was extended from the original sunset date of December 31, 2022 when the FASB issued ASU No. 2022-06 in December 2022. The guidance may be elected over time as reference rate reform activities occur. During the first quarter of 2020, the Company elected to apply the hedge accounting expedients related to probability and the assessments of effectiveness for future LIBOR-indexed cash flows to assume that the index upon which future hedged transactions will be based matches the index on the corresponding derivatives. Application of these expedients preserves the presentation of derivatives consistent with past presentation. The impact of this guidance did not have a material impact on the Company's consolidated financial statements.

Stockholders' Equity of the Company

9 Months Ended

Sep. 30, 2024

Stockholders' Equity Note [Abstract]

Stockholders' Equity of the Company

Stockholders’ Equity of the Company

Common Stock

Share Repurchase Program

Our Board of Directors has approved a $3.5 billion share repurchase program under which we can buy shares of our common stock.

Perpetual Preferred Stock

Dividend Reinvestment and Stock Purchase Plan ("DRSPP")


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Shares of common stock issued	338,704		2,695		341,180		14,736
Dividend reinvestments/stock purchases under the DRSPP	$	23,633	$	97	$	23,754	$	439

Earnings per Share

SL Green's earnings per share for the three and nine months ended September 30, 2024 and 2023 are computed as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Numerator	2024		2023		2024		2023
Basic Earnings:
Loss attributable to SL Green common stockholders	$	(13,279)	$	(23,967)	$	(2,298)	$	(423,892)
Less: distributed earnings allocated to participating securities	(435)		(408)		(1,309)		(1,225)

Net loss attributable to SL Green common stockholders (numerator for basic earnings per share)	$	(13,714)	$	(24,375)	$	(3,607)	$	(425,117)
Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares	—		—		—		—

Add back: effect of dilutive securities (redemption of units to common shares)	—		(1,574)		—		(27,493)
Net loss attributable to SL Green common stockholders (numerator for diluted earnings per share)	$	(13,714)	$	(25,949)	$	(3,607)	$	(452,610)


	Three Months Ended September 30,		Nine Months Ended September 30,
Denominator	2024	2023	2024	2023
Basic Shares:
Weighted average common stock outstanding	64,388	64,114	64,355	64,099
Effect of Dilutive Securities:
Operating Partnership units redeemable for common shares	—	4,182	—	4,175


Diluted weighted average common stock outstanding	64,388	68,296	64,355	68,274

Partners' Capital of the Operating Partnership

Net income (loss) allocated to the preferred unitholders and common unitholders reflects their pro rata share of net income (loss) and distributions.

Limited Partner Units

As of September 30, 2024, limited partners, other than SL Green, owned 6.42%, or 4,474,406 common units, of the Operating Partnership.

Preferred Units

Earnings per Unit

The Operating Partnership's earnings per unit for the three and nine months ended September 30, 2024 and 2023, respectively, are computed as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
Numerator	2024		2023		2024		2023
Basic Earnings:
Net loss attributable to SLGOP common unitholders	$	(14,193)	$	(25,541)	$	(2,464)	$	(451,385)
Less: distributed earnings allocated to participating securities	(1,147)		(408)		(3,415)		(1,225)

Net loss attributable to SLGOP common unitholders (numerator for basic earnings per unit)	$	(15,340)	$	(25,949)	$	(5,879)	$	(452,610)


Net loss attributable to SLGOP common unitholders (numerator for diluted earnings per unit)	$	(15,340)	$	(25,949)	$	(5,879)	$	(452,610)


	Three Months Ended September 30,		Nine Months Ended September 30,
Denominator	2024	2023	2024	2023
Basic units:
Weighted average common units outstanding	67,999	68,296	68,092	68,274



Diluted weighted average common units outstanding	67,999	68,296	68,092	68,274

Accumulated Other Comprehensive Income

The following tables set forth the changes in accumulated other comprehensive income by component as of September 30, 2024 (in thousands):


	Net unrealized gain (loss) on derivative instruments (1)		SL Green’s share of joint venture net unrealized loss on derivative instruments (2)		Net unrealized (loss) gain on marketable securities		Total
Balance at December 31, 2023	$	25,352	$	(6,084)	$	(1,791)	$	17,477
Other comprehensive (loss) income before reclassifications	3,864		(11,035)		1,103		(6,068)
Amounts reclassified from accumulated other comprehensive (loss) income	(27,921)		(10,796)		—		(38,717)
Balance at September 30, 2024	$	1,295	$	(27,915)	$	(688)	$	(27,308)

- Definition

The entire disclosure for equity.

+ References

+ Details

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Expenses
Operating expenses	$ 49,507	$ 49,585	$ 139,448	$ 148,606
Related party
Expenses
Operating expenses	$ 0	$ 2	$ 2	$ 3

Consolidated Balance Sheets (Partnership) - USD ($)
$ in Thousands

Sep. 30, 2024

Dec. 31, 2023

Commercial real estate properties, at cost:

Land and land interests

$ 1,134,432

$ 1,092,671

Building and improvements

3,781,403

3,655,624

Building leasehold and improvements

1,374,059

1,354,569

Real Estate Investment Property, at Cost

6,289,894

6,102,864

Less: accumulated depreciation

(2,084,755)

(1,968,004)

Real Estate Investment Property, Net

4,205,139

4,134,860

Cash and cash equivalents

188,216

221,823

Restricted cash

126,909

113,696

Investments in marketable securities

16,522

9,591

Tenant and other receivables

53,628

33,270

Related party receivables

13,077

12,168

Deferred rents receivable

266,606

264,653

Carrying Value

293,924

346,745

Company's investments in unconsolidated joint ventures

2,871,683

2,983,313

Deferred costs, net

105,646

111,463

Right-of-use assets - operating leases

870,782

885,929

Real estate loans held by consolidated securitization vehicles (includes $586,823 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

713,218

Other assets

490,722

413,670

Total assets

^[1]

10,216,072

9,531,181

Liabilities

Mortgages and other loans payable, net

1,643,992

1,491,319

Revolving credit facility, net

730,851

554,752

Unsecured term loans, net

1,246,180

1,244,881

Unsecured notes, net

99,872

99,795

Accrued interest payable

22,825

17,930

Senior obligations of consolidated securitization vehicles (includes $571,711 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

603,902

Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

409,844

471,401

Accounts payable and accrued expenses

125,377

153,164

Deferred revenue

154,700

134,053

Lease liability - financing leases

106,518

105,531

Lease liability - operating leases

815,238

827,692

Dividend and distributions payable

20,147

20,280

Security deposits

56,297

49,906

Junior subordinated deferrable interest debentures held by trusts that issued trust preferred securities

100,000

Liabilities

^[1]

6,135,743

5,270,704

Commitments and contingencies

Preferred units

166,731

166,501

Capital

Accumulated other comprehensive (loss) income

(27,308)

17,477

Total liabilities and equity

10,216,072

9,531,181

SL Green Operating Partnership

Commercial real estate properties, at cost:

Land and land interests

1,134,432

1,092,671

Building and improvements

3,781,403

3,655,624

Building leasehold and improvements

1,374,059

1,354,569

Real Estate Investment Property, at Cost

6,289,894

6,102,864

Less: accumulated depreciation

(2,084,755)

(1,968,004)

Real Estate Investment Property, Net

4,205,139

4,134,860

Cash and cash equivalents

188,216

221,823

Restricted cash

126,909

113,696

Investments in marketable securities

16,522

9,591

Tenant and other receivables

53,628

33,270

Related party receivables

13,077

12,168

Deferred rents receivable

266,606

264,653

Carrying Value

293,924

346,745

Company's investments in unconsolidated joint ventures

2,871,683

2,983,313

Deferred costs, net

105,646

111,463

Right-of-use assets - operating leases

870,782

885,929

Real estate loans held by consolidated securitization vehicles (includes $586,823 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

713,218

Other assets

490,722

413,670

Total assets

^[2]

10,216,072

9,531,181

Liabilities

Mortgages and other loans payable, net

1,643,992

1,491,319

Revolving credit facility, net

730,851

554,752

Unsecured term loans, net

1,246,180

1,244,881

Unsecured notes, net

99,872

99,795

Accrued interest payable

22,825

17,930

Senior obligations of consolidated securitization vehicles (includes $571,711 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

603,902

Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)

409,844

471,401

Accounts payable and accrued expenses

125,377

153,164

Deferred revenue

154,700

134,053

Lease liability - financing leases

106,518

105,531

Lease liability - operating leases

815,238

827,692

Dividend and distributions payable

20,147

20,280

Security deposits

56,297

49,906

Junior subordinated deferrable interest debentures held by trusts that issued trust preferred securities

100,000

Liabilities

^[2]

6,135,743

5,270,704

Commitments and contingencies

Limited partner interests in SLGOP (4,474 and 3,949 limited partner common units outstanding at September 30, 2024 and December 31, 2023, respectively)

293,593

238,051

Preferred units

166,731

166,501

Capital

Series I Preferred Units, $25.00 liquidation preference, 9,200 issued and outstanding at both June 30, 2024 and December 31, 2023

221,932

SL Green partners' capital (694 and 687 general partner common units and 64,541 and 64,039 limited partner common units outstanding at September 30, 2024 and December 31, 2023, respectively)

3,361,661

3,546,906

Accumulated other comprehensive (loss) income

(27,308)

17,477

Total SLGOP partners' capital

3,556,285

3,786,315

Noncontrolling interests in other partnerships

63,720

69,610

Total capital

3,620,005

3,855,925

Total liabilities and equity

$ 10,216,072

$ 9,531,181

[1]

[2]

(1) The Operating Partnership's consolidated balance sheets include assets and liabilities of consolidated variable interest entities ("VIEs"). See Note 2. The consolidated balance sheets include the following amounts related to our consolidated VIEs, excluding the Operating Partnership: $104.1 million and $41.2 million of land, $65.4 million and $40.5 million of building and improvements, $— million and $— million of building and leasehold improvements, $— million and $— million of right of use assets, $3.2 million and $5.4 million of accumulated depreciation, $713.2 million and $— million of real estate loans held by consolidated securitization vehicles, $776.3 million and $676.9 million of other assets included in other line items, $204.3 million and $50.0 million of real estate debt, net, $0.9 million and $0.9 million of accrued interest payable, $— million and $— million of lease liabilities, $603.9 million and $— million of senior obligations of consolidated securitization vehicles and $308.0 million and $306.5 million of other liabilities included in other line items as of September 30, 2024 and December 31, 2023, respectively.

Consolidated Statements of Cash Flows (Partnership) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Operating Activities
Net income (loss)	$ 11,084	$ (439,279)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	158,892	205,086
Equity in net (income) loss from unconsolidated joint ventures	(100,057)	44,470
Distributions of cumulative earnings from unconsolidated joint ventures	306	514
Equity in net (gain) loss on sale of interest in unconsolidated joint venture interest/real estate	(19,006)	79
Purchase price and other fair value adjustments	36,321	6,987
Depreciable real estate reserves and impairment	65,839	305,527
(Gain) loss on sale of real estate, net	(4,730)	27,813
Loan loss reserves and other investment reserves, net of recoveries	0	6,890
Gain on early extinguishment of debt	(17,777)	0
Deferred rents receivable	(2,166)	(16,195)
Non-cash lease expense	15,147	15,477
Other non-cash adjustments	31,460	6,645
Changes in operating assets and liabilities:
Tenant and other receivables	(12,693)	(2,852)
Related party receivables	181	16,466
Deferred lease costs	(11,920)	(8,066)
Other assets	(11,332)	(14,169)
Accounts payable, accrued expenses, other liabilities and security deposits	(57,291)	23,655
Deferred revenue	1,616	9,978
Lease liability - operating leases	(12,454)	(7,688)
Net Cash Provided by (Used in) Operating Activities	71,420	181,338
Investing Activities
Additions to land, buildings and improvements	(162,691)	(194,035)
Acquisition deposits and deferred purchase price	(12,817)	0
Investments in unconsolidated joint ventures	(371,948)	(119,522)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	99,307	108,884
Net proceeds from disposition of real estate/joint venture interest	478,151	547,605
Investments in marketable securities	(5,604)	0
Investments in real estate loans held by consolidated securitization vehicles	(108,893)
Other investments	(7,350)	(17,545)
Origination of debt and preferred equity investments	(9,126)	(53,703)
Repayments or redemption of debt and preferred equity investments	63,496	0
Net Cash Provided by (Used in) Investing Activities	(37,475)	271,684
Financing Activities
Proceeds from mortgages and other loans payable	900	0
Repayments of mortgages and other loans payable	(36,488)	(4,340)
Proceeds from revolving credit facility, term loans and unsecured notes	920,000	358,000
Repayments of revolving credit facility, term loans and unsecured notes	(745,000)	(808,000)
Proceeds from stock options exercised and DRSPP issuance	14,291	439
Redemption of preferred units	0	(11,700)
Redemption of OP units	(31,491)	(8,900)
Distributions to noncontrolling interests in other partnerships	(4,567)	(1,614)
Contributions from noncontrolling interests in other partnerships	1,823	3,580
Distributions paid on common and preferred units	(162,787)	(172,920)
Other obligations related to secured borrowing	0	129,656
Deferred loan costs	(475)	(729)
Net cash used in financing activities	(54,339)	(527,753)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(20,394)	(74,731)
Cash, cash equivalents, and restricted cash at beginning of year	335,519	384,054
Cash, cash equivalents, and restricted cash at end of period	315,125	309,323
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Exchange of debt investment for real estate or equity in joint venture	0	349,946
Fair value adjustment to noncontrolling interest in the Operating Partnership	77,400	8,072
Investment in joint venture	10,639	0
Consolidation of a subsidiary	6,678	0
Consolidation of mortgage loan payable	205,000	0
Acquisition of subsidiary interest from noncontrolling interest	5,674	0
Contribution to consolidated joint venture interest	0	8,134
Extinguishment of debt	18,000	0
Debt and preferred equity investments	1,133	0
Removal of fully depreciated commercial real estate properties	4,774	7,747
Share repurchase or redemption payable	9,514	0
Consolidation of securitization vehicle assets	600,521	0
Consolidation of securitization vehicle liabilities	600,521	0
Restricted cash	126,909	119,573
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	315,125	309,323
Cash and cash equivalents	188,216	189,750
SL Green Operating Partnership
Operating Activities
Net income (loss)	11,084	(439,279)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	158,892	205,086
Equity in net (income) loss from unconsolidated joint ventures	(100,057)	44,470
Distributions of cumulative earnings from unconsolidated joint ventures	306	514
Equity in net (gain) loss on sale of interest in unconsolidated joint venture interest/real estate	(19,006)	79
Purchase price and other fair value adjustments	36,321	6,987
Depreciable real estate reserves and impairment	65,839	305,527
(Gain) loss on sale of real estate, net	(4,730)	27,813
Loan loss reserves and other investment reserves, net of recoveries	0	6,890
Gain on early extinguishment of debt	(17,777)	0
Deferred rents receivable	(2,166)	(16,195)
Non-cash lease expense	15,147	15,477
Other non-cash adjustments	31,460	6,645
Changes in operating assets and liabilities:
Tenant and other receivables	(12,693)	(2,852)
Related party receivables	181	16,466
Deferred lease costs	(11,920)	(8,066)
Other assets	(11,332)	(14,169)
Accounts payable, accrued expenses, other liabilities and security deposits	(57,291)	23,655
Deferred revenue	1,616	9,978
Lease liability - operating leases	(12,454)	(7,688)
Net Cash Provided by (Used in) Operating Activities	71,420	181,338
Investing Activities
Additions to land, buildings and improvements	(162,691)	(194,035)
Acquisition deposits and deferred purchase price	(12,817)	0
Investments in unconsolidated joint ventures	(371,948)	(119,522)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	99,307	108,884
Net proceeds from disposition of real estate/joint venture interest	478,151	547,605
Investments in marketable securities	(5,604)	0
Investments in real estate loans held by consolidated securitization vehicles	(108,893)	0
Other investments	(7,350)	(17,545)
Origination of debt and preferred equity investments	(9,126)	(53,703)
Repayments or redemption of debt and preferred equity investments	63,496	0
Net Cash Provided by (Used in) Investing Activities	(37,475)	271,684
Financing Activities
Proceeds from mortgages and other loans payable	900	0
Repayments of mortgages and other loans payable	(36,488)	(4,340)
Proceeds from revolving credit facility, term loans and unsecured notes	920,000	358,000
Repayments of revolving credit facility, term loans and unsecured notes	(745,000)	(808,000)
Proceeds from stock options exercised and DRSPP issuance	14,291	439
Redemption of preferred units	0	(11,700)
Redemption of OP units	(31,491)	(8,900)
Distributions to noncontrolling interests in other partnerships	(4,567)	(1,614)
Contributions from noncontrolling interests in other partnerships	1,823	3,580
Distributions paid on common and preferred units	(173,332)	(184,145)
Other obligations related to secured borrowing	0	129,656
Deferred loan costs	(475)	(729)
Net cash used in financing activities	(54,339)	(527,753)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(20,394)	(74,731)
Cash, cash equivalents, and restricted cash at end of period	315,125	309,323
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Exchange of debt investment for real estate or equity in joint venture	0	349,946
Fair value adjustment to noncontrolling interest in the Operating Partnership	77,400	8,072
Investment in joint venture	10,639	0
Deconsolidation of a subsidiary	0	101,351
Consolidation of a subsidiary	6,678	0
Consolidation of mortgage loan payable	205,000	0
Acquisition of subsidiary interest from noncontrolling interest	5,674	0
Contribution to consolidated joint venture interest	0	8,134
Extinguishment of debt	18,000	0
Debt and preferred equity investments	1,133	0
Removal of fully depreciated commercial real estate properties	4,774	7,747
Share repurchase or redemption payable	9,514	0
Consolidation of securitization vehicle assets	600,521	0
Consolidation of securitization vehicle liabilities	600,521	0
Restricted cash	126,909	119,573
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	315,125	309,323
Cash and cash equivalents	$ 188,216	$ 189,750

Consolidated Balance Sheets (Partnership) (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Assets
Debt and preferred equity investments, discount and deferred origination fees	$ 1,618	$ 1,630
Allowance for loan and lease losses, real estate	13,520	13,520
Real estate loans held by consolidated securitization vehicles	586,823	0
Liabilities
Senior obligations of consolidated securitization vehicles	571,711	0
Secured borrowings	237,454	0
Capital
Land and land interests	1,134,432	1,092,671
Building and improvements	3,781,403	3,655,624
Building leasehold and improvements	1,374,059	1,354,569
Right-of-use assets - operating leases	870,782	885,929
Accumulated depreciation	2,084,755	1,968,004
Real estate loans held by consolidated securitization vehicles (includes $586,823 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	713,218	0
Other assets	490,722	413,670
Mortgages and other loans payable, net	1,643,992	1,491,319
Lease liability - financing leases	106,518	105,531
Senior obligations of consolidated securitization vehicles (includes $571,711 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	603,902	0
Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	409,844	471,401
SL Green Operating Partnership
Assets
Debt and preferred equity investments, discount and deferred origination fees	1,618	1,630
Allowance for loan and lease losses, real estate	13,520	13,520
Real estate loans held by consolidated securitization vehicles	586,823	0
Liabilities
Senior obligations of consolidated securitization vehicles	571,711	0
Secured borrowings	$ 237,454	$ 0
Limited partner interests in Operating Partnership, limited partner common units outstanding (shares)	4,474	3,949
Capital
SL Green partner's capital, general partner common units outstanding (shares)	694	687
SL Green partners' capital, limited partner common units outstanding (shares)	64,541	64,039
Land and land interests	$ 1,134,432	$ 1,092,671
Building and improvements	3,781,403	3,655,624
Building leasehold and improvements	1,374,059	1,354,569
Right-of-use assets - operating leases	870,782	885,929
Accumulated depreciation	2,084,755	1,968,004
Real estate loans held by consolidated securitization vehicles (includes $586,823 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	713,218	0
Other assets	490,722	413,670
Mortgages and other loans payable, net	1,643,992	1,491,319
Lease liability - financing leases	106,518	105,531
Senior obligations of consolidated securitization vehicles (includes $571,711 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	603,902	0
Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	409,844	471,401
Service Corporation
Capital
Land and land interests	104,100	41,200
Building and improvements	65,400	40,500
Building leasehold and improvements	0	0
Right-of-use assets - operating leases	0	0
Accumulated depreciation	3,200	5,400
Real estate loans held by consolidated securitization vehicles (includes $586,823 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	713,200	0
Other assets	776,300	676,900
Mortgages and other loans payable, net	204,300	50,000
Accrued interest payable	900	900
Lease liability - financing leases	0	0
Senior obligations of consolidated securitization vehicles (includes $571,711 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	603,900	0
Other liabilities (includes $237,454 and $— at fair value as of September 30, 2024 and December 31, 2023, respectively)	$ 308,000	$ 306,500
Series I Preferred Stock \| SL Green Operating Partnership
Capital
Preferred units, liquidation preference (in dollars per share)	$ 25.00	$ 25.00
Preferred units, shares issued (in shares)	9,200	9,200
Preferred units, shares outstanding (in shares)	9,200	9,200

Noncontrolling Interests on the Company's Consolidated Financial Statements - Schedule of Common Unit Activity (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Rollforward Analysis of Preferred Unit Activity
Contributions to consolidated joint venture interests	$ 1,823
Redemption of preferred units	(5,674)
SL Green Operating Partnership
Rollforward Analysis of Preferred Unit Activity
Contributions to consolidated joint venture interests	1,823
Redemption of preferred units	(5,674)
SL Green Operating Partnership \| Preferred stock
Rollforward Analysis of Preferred Unit Activity
Balance at beginning of period	166,501	$ 177,943
Contributions to consolidated joint venture interests	0	0
Redemption of preferred units	0	(11,700)
Dividends paid on preferred units	(3,916)	(6,271)
Accrued dividends on preferred units	4,146	6,529
Balance at end of period	$ 166,731	$ 166,501

Organization and Basis of Presentation - Schedule of Commercial Office Properties (Details)	Sep. 30, 2024 ft² building
Commercial properties
Real estate properties
Number of Buildings \| building	36
Approximate Square Feet unaudited (sqft)	24,927,239
Weighted Average Leased Occupancy	89.30%
Core portfolio
Real estate properties
Number of Buildings \| building	38
Approximate Square Feet unaudited (sqft)	25,289,505
Consolidated \| Commercial properties
Real estate properties
Number of Buildings \| building	24
Approximate Square Feet unaudited (sqft)	10,519,660
Consolidated \| Core portfolio
Real estate properties
Number of Buildings \| building	25
Approximate Square Feet unaudited (sqft)	10,660,042
Unconsolidated \| Commercial properties
Real estate properties
Number of Buildings \| building	12
Approximate Square Feet unaudited (sqft)	14,407,579
Unconsolidated \| Core portfolio
Real estate properties
Number of Buildings \| building	13
Approximate Square Feet unaudited (sqft)	14,629,463
Manhattan
Real estate properties
Number of Buildings \| building	29
Approximate Square Feet unaudited (sqft)	24,064,439
Weighted Average Leased Occupancy	89.90%
Manhattan \| Office
Real estate properties
Number of Buildings \| building	24
Approximate Square Feet unaudited (sqft)	21,762,590
Weighted Average Leased Occupancy	89.90%
Manhattan \| Retail
Real estate properties
Number of Buildings \| building	2
Approximate Square Feet unaudited (sqft)	35,594
Weighted Average Leased Occupancy	100.00%
Manhattan \| Development/Redevelopment
Real estate properties
Number of Buildings \| building	3
Approximate Square Feet unaudited (sqft)	2,266,255
Manhattan \| Residential
Real estate properties
Number of Buildings \| building	2
Approximate Square Feet unaudited (sqft)	362,266
Weighted Average Leased Occupancy	99.00%
Manhattan \| Core portfolio
Real estate properties
Weighted Average Leased Occupancy	89.40%
Manhattan \| Alternative Strategy Portfolio (3)
Real estate properties
Number of Buildings \| building	9
Approximate Square Feet unaudited (sqft)	3,702,804
Weighted Average Leased Occupancy	49.40%
Manhattan \| Consolidated
Real estate properties
Number of Buildings \| building	17
Approximate Square Feet unaudited (sqft)	9,656,860
Manhattan \| Consolidated \| Office
Real estate properties
Number of Buildings \| building	14
Approximate Square Feet unaudited (sqft)	8,753,441
Manhattan \| Consolidated \| Retail
Real estate properties
Number of Buildings \| building	1
Approximate Square Feet unaudited (sqft)	22,648
Manhattan \| Consolidated \| Retail \| 7 Dey / 185 Broadway
Real estate properties
Approximate Square Feet unaudited (sqft)	140,382
Manhattan \| Consolidated \| Development/Redevelopment
Real estate properties
Number of Buildings \| building	2
Approximate Square Feet unaudited (sqft)	880,771
Manhattan \| Consolidated \| Residential
Real estate properties
Number of Buildings \| building	1
Approximate Square Feet unaudited (sqft)	140,382
Manhattan \| Consolidated \| Residential \| 7 Dey / 185 Broadway
Real estate properties
Approximate Square Feet unaudited (sqft)	50,206
Manhattan \| Consolidated \| Alternative Strategy Portfolio (3)
Real estate properties
Number of Buildings \| building	1
Approximate Square Feet unaudited (sqft)	7,848
Manhattan \| Unconsolidated
Real estate properties
Number of Buildings \| building	12
Approximate Square Feet unaudited (sqft)	14,407,579
Manhattan \| Unconsolidated \| Office
Real estate properties
Number of Buildings \| building	10
Approximate Square Feet unaudited (sqft)	13,009,149
Manhattan \| Unconsolidated \| Retail
Real estate properties
Number of Buildings \| building	1
Approximate Square Feet unaudited (sqft)	12,946
Manhattan \| Unconsolidated \| Development/Redevelopment
Real estate properties
Number of Buildings \| building	1
Approximate Square Feet unaudited (sqft)	1,385,484
Manhattan \| Unconsolidated \| Residential
Real estate properties
Number of Buildings \| building	1
Approximate Square Feet unaudited (sqft)	221,884
Manhattan \| Unconsolidated \| Alternative Strategy Portfolio (3)
Real estate properties
Number of Buildings \| building	8
Approximate Square Feet unaudited (sqft)	3,694,956
Suburban \| Office
Real estate properties
Number of Buildings \| building	7
Approximate Square Feet unaudited (sqft)	862,800
Weighted Average Leased Occupancy	73.60%
Suburban \| Consolidated \| Office
Real estate properties
Number of Buildings \| building	7
Approximate Square Feet unaudited (sqft)	862,800
Suburban \| Unconsolidated \| Office
Real estate properties
Number of Buildings \| building	0
Approximate Square Feet unaudited (sqft)	0