0001040971-24-000010 | 10-K | XBRL Viewer

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Significant Accounting Policies - Schedule of Estimated Annual Amortization of all Other Identifiable Assets (Details) - Other Identifiable Assets $ in Thousands	Dec. 31, 2023 USD ($)
Real Estate [Line Items]
2024	$ 1,096
2025	728
2026	551
2027	312
2028	$ 158

Deferred Costs (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred leasing costs	$ 399,224	$ 407,188
Less: accumulated amortization	(287,761)	(286,031)
Deferred costs, net	$ 111,463	$ 121,157

Corporate Indebtedness (Tables)

12 Months Ended

Dec. 31, 2023

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 December 31, 2023 and 2022, respectively, by scheduled maturity date (dollars in thousands):


	December 31, 2023				December 31, 2022
Issuance	Unpaid Principal Balance		Accreted Balance		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	—		(205)		(308)
	$	100,000	$	99,795	$	99,692

(1)Interest rate as of December 31, 2023.

(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 December 31, 2023, including as-of-right extension options, were as follows (in thousands):


	Scheduled Amortization		Principal		Revolving Credit Facility		Unsecured Term Loans		Trust Preferred Securities		Senior Unsecured Notes		Total		Company's Share of Joint Venture Debt
2024	$	4,488	$	382,750	$	—	$	200,000	$	—	$	—	$	587,238	$	1,822,978
2025	—		370,000		—		—		—		100,000		470,000		1,670,861
2026	—		190,148		—		—		—		—		190,148		542,968
2027	—		550,000		560,000		1,050,000		—		—		2,160,000		1,185,168
2028	—		—		—		—		—		—		—		—
Thereafter	—		—		—		—		100,000		—		100,000		2,130,300
Total	$	4,488	$	1,492,898	$	560,000	$	1,250,000	$	100,000	$	100,000	$	3,507,386	$	7,352,275

Schedule of consolidated interest expense, excluding capitalized interest

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


	Year Ended December 31,
	2023		2022		2021
Interest expense before capitalized interest	$	228,840	$	166,493	$	145,197
Interest on financing leases	4,446		4,555		5,448
Interest capitalized	(95,980)		(82,444)		(78,365)
Amortization of discount on assumed debt	2,842		1,855		—
Interest income	(3,034)		(986)		(1,389)
Interest expense, net	$	137,114	$	89,473	$	70,891

- 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

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+ Details

Consolidated Statements of Cash Flows (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash distribution declared, per common share (in dollars per share)	$ 3.2288	$ 3.6896	$ 6.2729
Ordinary Dividend
Cash distribution declared, per common share (in dollars per share)	$ 0.2500	$ 0.2708	0.3108
Special Dividend
Cash distribution declared, per common share (in dollars per share)			$ 2.4392

Debt and Preferred Equity Investments (Tables)

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Schedule of Activity in Debt and Preferred Equity Investments

Below is a summary of the activity in our debt and preferred equity investments for the years ended December 31, 2023 and 2022 (in thousands):


	December 31, 2023			December 31, 2022
Balance at beginning of year (1)	$	623,280		$	1,088,723
Debt investment originations/fundings/accretion (2)	72,160			62,992
Preferred equity investment originations/accretion (2)	8,142			37,505
Redemptions/sales/syndications/equity ownership/amortization	(349,947)			(565,940)
Net change in loan loss reserves	(6,890)			—
Balance at end of period (1)	$	346,745	(3)	$	623,280

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

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

(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 Debt and Preferred Equity Investments

Below is a summary of our debt and preferred equity investments as of December 31, 2023 (dollars in thousands):


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

Mezzanine Debt	$	168,745	$	168,912	S + 4.95 - 12.38%	$	50,000	$	50,000	8.00 - 8.40%	$	218,745	(2)	$	1,071,858	2024 - 2029
Preferred Equity	—		—		—	128,000		128,000		6.5%	128,000			250,000		2027
Balance at end of period	$	168,745	$	168,912		$	178,000	$	178,000		$	346,745		$	1,321,858

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

(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 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 years ended December 31, 2023, 2022 and 2021 (in thousands):


	Year Ended December 31,
	2023			2022		2021
Balance at beginning of year	$	6,630		$	6,630	$	13,213
Current period provision for loan loss	6,890			—		—
Write-offs charged against the allowance	—			—		(6,583)
Balance at end of period	$	13,520	(1)	$	6,630	$	6,630

(1)As of December 31, 2023, all financing receivables 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.

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

The following table sets forth the carrying value of our debt and preferred equity investment portfolio by risk rating as of December 31, 2023 and 2022 (dollars in thousands):


Risk Rating	December 31, 2023			December 31, 2022
1 - Low Risk Assets - Low probability of loss	$	210,333		$	264,069
2 - Watch List Assets - Higher potential for loss	136,412		(1)	352,321
3 - High Risk Assets - Loss more likely than not	—			6,890
	$	346,745		$	623,280

(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 debt and preferred equity investment portfolio by year of origination and risk rating as of December 31, 2023 (dollars in thousands):


	As of December 31,
Risk Rating	2023(1)		2022(1)		2021(1)		Prior(1)(2)			Total
1 - Low Risk Assets - Low probability of loss	$	—	$	—	$	—	$	210,333		$	210,333
2 - Watch List Assets - Higher potential for loss	—		—		—		136,412		(3)	136,412
3 - High Risk Assets - Loss more likely than not	—		—		—		—			—
	$	—	$	—	$	—	$	346,745		$	346,745

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

(2)During the year ended December 31, 2023, we recognized a $6.9 million provision for loan loss related to an investment originated prior to 2021.

(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 Debt Investments with an Aggregate Weighted Average Current Yield

As of December 31, 2023 and 2022, we held the following debt investments with an aggregate weighted average current yield of 8.68% as of December 31, 2023 (dollars in thousands):


	December 31, 2023						December 31, 2022
Loan Type	Future Funding Obligations		Senior Financing		Carrying Value (1)		Carrying Value (1)		Maturity Date (2)
Fixed Rate Investments:
Mezzanine Loan (3) (4) (6)	$	—	$	105,000	$	13,366	$	13,366	June 2024
Mezzanine Loan	—		95,000		30,000		30,000		January 2025
Mezzanine Loan	—		85,000		20,000		20,000		December 2029
Mezzanine Loan	—		—		—		225,367
Mezzanine Loan	—		—		—		77,109
Total fixed rate	$	—	$	285,000	$	63,366	$	365,842
Floating Rate Investments:
Mezzanine Loan (5) (6)	$	—	$	275,000	$	50,000	$	50,000	April 2023
Mezzanine Loan	3,761		54,000		8,243		8,243		May 2024
Mezzanine Loan	2,655		271,774		62,333		46,884		May 2024
Mezzanine Loan	10,760		186,084		48,323		39,083		January 2026





Total floating rate	$	17,176	$	786,858	$	168,899	$	144,210
Allowance for loan loss	$	—	$	—	$	(13,520)	$	(6,630)
Total	$	17,176	$	1,071,858	$	218,745	$	503,422

(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, which is included in Other assets and Other liabilities on the consolidated balance sheets.

(4)This loan went into default and was put on non-accrual in June 2020 and remains on non-accrual as of December 31, 2023. 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 December 31, 2023. 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.

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

As of December 31, 2023 and 2022, we held the following preferred equity investments with an aggregate weighted average current yield of 6.55% as of December 31, 2023 (dollars in thousands):


	December 31, 2023						December 31, 2022
Type	Future Funding Obligations		Senior Financing		Carrying Value (1)		Carrying Value (1)		Mandatory Redemption (2)
Preferred Equity	$	—	$	250,000	$	128,000	$	119,858	February 2027



Total	$	—	$	250,000	$	128,000	$	119,858

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

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

Mortgages and Other Loans Payable - Narrative (Details) - USD ($) $ in Billions	Dec. 31, 2023	Dec. 31, 2022
Mortgages and Other Loans Payable
Book value of collateral	$ 1.9	$ 3.8

Debt and Preferred Equity Investments - Schedule of Debt Investments with an Aggregate Weighted Average Current Yield (Details) - USD ($)	12 Months Ended	41 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate, interest rate	8.68%
Debt Investments Held [Abstract]
Carrying value at fixed rate	$ 346,745,000	$ 346,745,000	$ 623,280,000
Carrying Value	346,745,000	346,745,000	623,280,000
Allowance for loan loss	(13,520,000)	(13,520,000)	(6,630,000)	$ (6,630,000)	$ (13,213,000)
Loan interest income		0
Mezzanine Loan Due June 2024
Debt Investments Held [Abstract]
Amount participated out	12,000,000	12,000,000
Debt Investment
Debt Investments Held [Abstract]
Future funding obligations	17,176,000	17,176,000
Senior financing	1,071,858,000	1,071,858,000
Carrying Value	218,745,000	218,745,000	503,422,000
Allowance for loan loss	(13,520,000)	(13,520,000)	(6,630,000)
Total fixed rate
Debt Investments Held [Abstract]
Future funding obligations	0	0
Senior financing	285,000,000	285,000,000
Carrying value at fixed rate	63,366,000	63,366,000	365,842,000
Total fixed rate \| Mezzanine Loan Due June 2023
Debt Investments Held [Abstract]
Future funding obligations	0	0
Senior financing	105,000,000	105,000,000
Carrying value at fixed rate	13,366,000	13,366,000	13,366,000
Total fixed rate \| Mezzanine Loan Due June 2024, 2
Debt Investments Held [Abstract]
Future funding obligations	0	0
Senior financing	95,000,000	95,000,000
Carrying value at fixed rate	30,000,000	30,000,000	30,000,000
Total fixed rate \| Mezzanine Loan Due June 2024
Debt Investments Held [Abstract]
Future funding obligations	0	0
Senior financing	85,000,000	85,000,000
Carrying value at fixed rate	20,000,000	20,000,000	20,000,000
Total fixed rate \| Mezzanine Loan Due January 2025
Debt Investments Held [Abstract]
Future funding obligations	0	0
Senior financing	0	0
Carrying value at fixed rate	0	0	225,367,000
Total fixed rate \| Mezzanine Loan Due December 2029
Debt Investments Held [Abstract]
Future funding obligations	0	0
Senior financing	0	0
Carrying value at fixed rate	0	0	77,109,000
Total floating rate
Debt Investments Held [Abstract]
Future funding obligations	17,176,000	17,176,000
Senior financing	786,858,000	786,858,000
Carrying Value	168,899,000	168,899,000	144,210,000
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
Total floating rate \| Mezzanine Loan Due May 2023
Debt Investments Held [Abstract]
Future funding obligations	3,761,000	3,761,000
Senior financing	54,000,000	54,000,000
Carrying Value	8,243,000	8,243,000	8,243,000
Total floating rate \| Mezzanine Loan Due May 2023, 2
Debt Investments Held [Abstract]
Future funding obligations	2,655,000	2,655,000
Senior financing	271,774,000	271,774,000
Carrying Value	62,333,000	62,333,000	46,884,000
Total floating rate \| Mezzanine Loan Due July 2023
Debt Investments Held [Abstract]
Future funding obligations	10,760,000	10,760,000
Senior financing	186,084,000	186,084,000
Carrying Value	$ 48,323,000	$ 48,323,000	$ 39,083,000

Deferred Costs (Tables)

12 Months Ended

Dec. 31, 2023

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

Schedule of Deferred Costs

Deferred costs as of December 31, 2023 and 2022 consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Deferred leasing costs	$	399,224	$	407,188
Less: accumulated amortization	(287,761)		(286,031)
Deferred costs, net	$	111,463	$	121,157

Lease Income - Sales Type Lease (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Leases [Abstract]
2024	$ 3,180
2025	3,228
2026	3,276
2027	3,325
2028	3,375
Thereafter	196,794
Total minimum lease payments	213,178
Amount representing interest	(107,544)
Investment in sales-type leases	$ 105,634

Debt and Preferred Equity Investments - Schedule of Activity in Debt and Preferred Equity Investments (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) investment	Dec. 31, 2022 USD ($) investment
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance at beginning of year	$ 623,280	$ 1,088,723
Redemptions/sales/syndications/equity ownership/amortization	(349,947)	(565,940)
Net change in loan loss reserves	(6,890)	0
Balance at end of period	$ 346,745	$ 623,280
Number of investments, nonperforming \| investment	2	1
Carrying Value	$ 346,745	$ 623,280
Total floating rate
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Carrying Value	168,899	144,210
Total floating rate \| Alternative strategy portfolio
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/fundings/accretion	72,160	62,992
Preferred Equity Investments
SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward]
Originations/fundings/accretion	$ 8,142	$ 37,505

Investments in Unconsolidated Joint Ventures - Schedule of Investments in Unconsolidated Joint Ventures Sold (Details) - USD ($)	1 Months Ended					12 Months Ended
	Feb. 28, 2023	Sep. 30, 2021	Jun. 30, 2021	Apr. 30, 2021	Mar. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
(Loss) Gain on Sale						$ (13,368,000)	$ (131,000)	$ (32,757,000)
Employee-related liabilities						$ 2,000,000	$ 0	$ 1,400,000
400 East 57th Street
Schedule of Equity Method Investments [Line Items]
Asset impairment loss				$ 5,700,000
Due from joint ventures \| 21 East 66th Street \| Wharton Properties
Schedule of Equity Method Investments [Line Items]
Ownership Interest Sold	32.28%
Gross Asset Valuation	$ 40,600,000
(Loss) Gain on Sale	$ (12,700,000)
Due from joint ventures \| 121 Greene Street \| Wharton Properties
Schedule of Equity Method Investments [Line Items]
Ownership Interest Sold	50.00%
Gross Asset Valuation	$ 14,000,000.0
(Loss) Gain on Sale	$ (300,000)
Due from joint ventures \| Stonehenge Portfolio
Schedule of Equity Method Investments [Line Items]
Gross Asset Valuation		$ 1,000,000.0
(Loss) Gain on Sale		$ 0
Due from joint ventures \| 400 East 57th Street \| BlackRock, Inc And Stonehenge Partners
Schedule of Equity Method Investments [Line Items]
Ownership Interest Sold			41.00%
Gross Asset Valuation			$ 133,500,000
(Loss) Gain on Sale			$ (1,000,000.0)
Due from joint ventures \| 605 West 42nd Street - Sky \| The Moinian Group
Schedule of Equity Method Investments [Line Items]
Ownership Interest Sold					20.00%
Gross Asset Valuation					$ 858,100,000
(Loss) Gain on Sale					$ 8,900,000
Due from joint ventures \| 55 West 46th Street - Tower 46 \| Prudential Real Estate Investors
Schedule of Equity Method Investments [Line Items]
Ownership Interest Sold					25.00%
Gross Asset Valuation					$ 275,000,000.0
(Loss) Gain on Sale					$ (15,200,000)

Significant Accounting Policies - Depreciation and Amortization of Right of Use Assets (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jul. 01, 2022	Jun. 30, 2022	Dec. 31, 2020
Franchisor Disclosure [Line Items]
Depreciation expense (including amortization of the capital lease asset)	$ 221,000,000	$ 190,100,000	$ 187,300,000
Carrying value of investment in leasehold interest	7,056,100,000	9,198,799,000	7,650,907,000			$ 7,355,079,000
Amortization of above and below Market Leases	14,200,000	$ 5,700,000	$ 4,200,000
625 Madison Avenue
Franchisor Disclosure [Line Items]
Operating lease rent				$ 20,250,000	$ 4,610,000
Write down of value in leasehold interest	249,500,000
Carrying value of investment in leasehold interest	$ 0

Properties Held for Sale and Property Dispositions

12 Months Ended

Dec. 31, 2023

Discontinued Operations and Disposal Groups [Abstract]

Properties Held for Sale and Property Dispositions

Properties Held for Sale

As of December 31, 2023 and 2022, no properties were classified as held for sale.

Property Dispositions

The following table summarizes the properties sold during the years ended December 31, 2023, 2022, and 2021:


Property	Disposition Date	Property Type	Unaudited Approximate Usable Square Feet	Sales Price (1) (in millions)		(Loss) Gain on Sale (2) (in millions)
245 Park Avenue (3)	June 2023	Fee Interest	1,782,793	$	1,995.0	$	(28.3)
885 Third Avenue - Office Condominium Units (4)	December 2022	Fee / Leasehold Interest	414,317	300.4		(24.0)
609 Fifth Avenue	June 2022	Fee Interest	138,563	100.5		(80.2)
1591-1597 Broadway	May 2022	Fee Interest	7,684	121.0		(4.5)
1080 Amsterdam Avenue	April 2022	Leasehold Interest	85,250	42.7		17.9
707 Eleventh Avenue	February 2022	Fee Interest	159,720	95.0		(0.8)
110 East 42nd Street	December 2021	Fee Interest	215,400	117.1		3.6
590 Fifth Avenue	October 2021	Fee Interest	103,300	103.0		(3.2)
220 East 42nd Street (5)	July 2021	Fee Interest	1,135,000	783.5		175.1
635-641 Sixth Avenue	June 2021	Fee Interest	267,000	325.0		99.4
106 Spring Street (6)	March 2021	Fee Interest	5,928	35.0		(2.8)
133 Greene Street (6)	February 2021	Fee Interest	6,425	15.8		0.2
712 Madison Avenue (7)	January 2021	Fee Interest	6,600	43.0		(1.4)

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

(2)The (losses) gains on sale are net of $11.3 million, $11.2 million, and $13.7 million of employee compensation accrued in connection with the realization of the investment dispositions during the years ended December 31, 2023, 2022, and 2021, respectively. Additionally, amounts do not include adjustments for expenses recorded in subsequent periods.

(3)In June 2023, the Company sold a 49.9% interest, which resulted in the Company no longer retaining a controlling interest in the entity, as defined in ASC 810, and deconsolidation of the 50.1% interest we retained. We recorded our retained investment at fair value which resulted in the recognition of a fair value adjustment of ($17.0 million) that is reflected in the Company's consolidated statements of operations within Purchase price and other fair value adjustments. See Note 6, "Investments in Unconsolidated Joint Venture" and Note 16, " Fair Value Measurements."

(4)In December 2022, the Company sold 414,317 square feet of office leasehold condominium units at the property. The Company retained the remaining 218,796 square feet of the building.

(5)In July 2021, the Company sold a 49.9% interest, which resulted in the Company no longer retaining a controlling interest in the entity, as defined in ASC 810, and the deconsolidation of the 51.0% interest we retained. We recorded our investment at fair value which resulted in the recognition of a fair value adjustment of $206.8 million, which is reflected in the Company's consolidated statements of operations within Purchase price and other fair value adjustments. See Note 6, "Investments in Unconsolidated Joint Ventures."

(6)In March 2021, the property was foreclosed by the lender.

(7)Disposition resulted from the ground lessee exercising its purchase option under a ground lease arrangement.

Segment Information - Additional Information (Details)
$ in Thousands

12 Months Ended

Dec. 31, 2023

USD ($)

segment

Dec. 31, 2022

USD ($)

Dec. 31, 2021

USD ($)

Segment information

Number of reportable segments (segment) | segment

Total revenues

$ 913,710

$ 919,454

$ 861,310

Net (loss) income

(599,337)

(76,303)

480,632

Total assets

^[1]

9,531,181

12,355,794

Marketing, general and administrative

111,389

93,798

94,912

Operating Segments | Real Estate

Segment information

Total revenues

760,745

749,293

764,659

Net (loss) income

(612,884)

(128,615)

413,401

Total assets

8,716,738

11,265,789

Operating Segments | SUMMIT

Segment information

Total revenues

118,260

89,048

16,311

Net (loss) income

6,101

(3,668)

(1,008)

Total assets

464,799

461,629

Operating Segments | Debt and Preferred Equity

Segment information

Total revenues

34,705

81,113

80,340

Net (loss) income

7,446

55,980

$ 68,239

Total assets

$ 349,644

$ 628,376

[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: $41.2 million and $41.2 million of land, $40.5 million and $41.0 million of building and improvements, $— million and $— million of building and leasehold improvements, $— million and $— million of right of use assets, $5.4 million and $4.4 million of accumulated depreciation, $676.9 million and $599.2 million of other assets included in other line items, $50.0 million and $49.8 million of real estate debt, net, $0.9 million and $0.2 million of accrued interest payable, $— million and $— million of lease liabilities, and $306.5 million and $146.4 million of other liabilities included in other line items as of December 31, 2023 and December 31, 2022, respectively.

Financial Instruments: Derivatives and Hedging (Tables)

12 Months Ended

Dec. 31, 2023

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 December 31, 2023 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 Swap	150,000	2.600	%	December 2021	January 2024	Other Assets	$	11
Interest Rate Swap	200,000	4.490	%	November 2022	January 2024	Other Assets	5
Interest Rate Swap	200,000	4.411	%	November 2022	January 2024	Other Assets	5
Interest Rate Cap	370,000	3.250	%	June 2023	June 2024	Other Assets	3,158
Interest Rate Cap	370,000	3.250	%	June 2023	June 2024	Other Liabilities	(3,145)
Interest Rate Swap	150,000	2.621	%	December 2021	January 2026	Other Assets	4,011
Interest Rate Swap	200,000	2.662	%	December 2021	January 2026	Other Assets	5,196
Interest Rate Swap	100,000	2.903	%	February 2023	February 2027	Other Assets	2,281
Interest Rate Swap	100,000	2.733	%	February 2023	February 2027	Other Assets	2,775
Interest Rate Swap	50,000	2.463	%	February 2023	February 2027	Other Assets	1,781
Interest Rate Swap	200,000	2.591	%	February 2023	February 2027	Other Assets	6,378
Interest Rate Swap	300,000	2.866	%	July 2023	May 2027	Other Assets	7,306
Interest Rate Swap	150,000	3.524	%	January 2024	May 2027	Other Assets	549
Interest Rate Swap	370,000	3.888	%	November 2022	June 2027	Other Liabilities	(3,044)
Interest Rate Swap	300,000	4.487	%	November 2024	November 2027	Other Liabilities	(10,273)
Interest Rate Swap	100,000	3.756	%	January 2023	January 2028	Other Liabilities	(646)
							$	16,348

The following table summarizes the notional value at inception and fair value of our joint ventures' derivative financial instruments as of December 31, 2023 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	$	220,000	4.000	%	February 2023	February 2024	Asset	$	318
Interest Rate Cap	484,069		0.490	%	February 2022	May 2024	Asset	8,331
Interest Rate Cap	484,069		0.490	%	February 2022	May 2024	Asset	8,330
Interest Rate Cap	505,412		3.000	%	June 2023	June 2024	Asset	4,948
Interest Rate Cap	272,000		4.000	%	August 2023	August 2024	Asset	1,675
Interest Rate Cap	477,783		3.500	%	September 2023	September 2024	Asset	5,213
Interest Rate Cap	278,161		4.000	%	May 2024	November 2024	Asset	948
Interest Rate Cap	278,161		4.000	%	May 2024	November 2024	Asset	948
Interest Rate Swap	250,000		3.608	%	April 2023	February 2026	Asset	1,819
Interest Rate Swap	250,000		3.608	%	April 2023	February 2026	Asset	1,818
Interest Rate Swap	177,000		1.555	%	December 2022	February 2026	Asset	8,686
								$	43,034

Schedule of effect of derivative financial instruments on consolidated statements of income

The following table presents 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 years ended December 31, 2023, 2022, and 2021, respectively (in thousands):


	Amount of Gain (Loss) Recognized in Other Comprehensive (Loss) Income						Location of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income	Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income
	Year Ended December 31,							Year Ended December 31,
Derivative	2023		2022		2021			2023		2022		2021
Interest Rate Swaps/Caps	$	18,484	$	83,162	$	15,643	Interest expense	$	42,270	$	4,989	$	(17,602)
Share of unconsolidated joint ventures' derivative instruments	7,399		24,783		(19,400)		Equity in net loss from unconsolidated joint ventures	16,050		(673)		(7,582)
	$	25,883	$	107,945	$	(3,757)		$	58,320	$	4,316	$	(25,184)

- 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

Significant Accounting Policies - Schedule of Estimated Useful Lives (Details)	Dec. 31, 2023
Building (fee ownership)
Real Estate [Line Items]
Estimated useful life (in years)	40 years
Building (leasehold interest) \| Maximum
Real Estate [Line Items]
Estimated useful life (in years)	40 years
Right of use assets - financing leases \| Maximum
Real Estate [Line Items]
Estimated useful life (in years)	40 years
Furniture and fixtures \| Maximum
Real Estate [Line Items]
Estimated useful life (in years)	7 years
Furniture and fixtures \| Minimum
Real Estate [Line Items]
Estimated useful life (in years)	4 years

Investments in Unconsolidated Joint Ventures - Schedule of General Information on Joint Ventures (Details)	1 Months Ended					12 Months Ended
	Jan. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) ft²	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($) ft²	Jul. 31, 2021 USD ($)	Dec. 31, 2023 USD ($) ft²	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
General information on each joint venture
Approximate Square Feet		29,695,841				29,695,841
Depreciable real estate reserves and impairments \| $						$ (382,374,000)	$ (6,313,000)	$ (23,794,000)
Mortgages and other loans payable, net \| $		$ 1,491,319,000				1,491,319,000	3,227,563,000
Repayments of mortgages \| $						25,826,000	292,364,000	$ 375,044,000
Ownership percentage deconsolidated				50.10%	51.00%
Investment fair value adjustment \| $				$ 17,000,000	$ 206,800,000	17,000,000
245 Park Avenue
General information on each joint venture
Approximate Square Feet				1,782,793
Gross asset valuation of property to be sold \| $				$ 1,995,000,000
Ownership interest disposed				49.90%
1552 Broadway
General information on each joint venture
Depreciable real estate reserves and impairments \| $		8,100,000
2 Herald Square
General information on each joint venture
Depreciable real estate reserves and impairments \| $		101,700,000
625 Madison Avenue
General information on each joint venture
Depreciable real estate reserves and impairments \| $			$ 23,100,000
Due from joint ventures
General information on each joint venture
Mortgages and other loans payable, net \| $		$ 14,799,277,000				$ 14,799,277,000	$ 12,348,954,000
Due from joint ventures \| 717 Fifth Avenue \| Subsequent Event
General information on each joint venture
Gross asset valuation of property to be sold \| $	$ 963,000,000
Due from joint ventures \| 2 Herald Square \| Subsequent Event
General information on each joint venture
Consideration transferred \| $	$ 0
Investment in joint venture, ownership percentage	95.00%
Mortgages and other loans payable, net \| $	$ 182,500,000
Repayments of mortgages \| $	$ 7,000,000
Prudential Real Estate Investors \| Due from joint ventures \| 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		834,000				834,000
Wharton Properties / Private Investor \| Due from joint ventures \| 717 Fifth Avenue
General information on each joint venture
Ownership Interest		10.92%				10.92%
Economic Interest (as a percent)		10.92%				10.92%
Approximate Square Feet		119,500				119,500
Private Investors \| Due from joint ventures \| 800 Third Avenue
General information on each joint venture
Ownership Interest		60.52%				60.52%
Economic Interest (as a percent)		60.52%				60.52%
Approximate Square Feet		526,000				526,000
Private Investors \| Due from joint ventures \| 115 Spring Street (2)
General information on each joint venture
Ownership Interest		51.00%				51.00%
Economic Interest (as a percent)		51.00%				51.00%
Approximate Square Feet		5,218				5,218
Private Investors \| Due from joint ventures \| 625 Madison Avenue
General information on each joint venture
Ownership Interest		90.43%				90.43%
Economic Interest (as a percent)		90.43%				90.43%
Approximate Square Feet		563,000				563,000
New York State Teacher's Retirement System \| Due from joint ventures \| 919 Third Avenue
General information on each joint venture
Ownership Interest		51.00%				51.00%
Economic Interest (as a percent)		51.00%				51.00%
Approximate Square Feet		1,454,000				1,454,000
Private Investor / Wharton Properties \| Due from joint ventures \| 11 West 34th Street (2)
General information on each joint venture
Ownership Interest		30.00%				30.00%
Economic Interest (as a percent)		30.00%				30.00%
Approximate Square Feet		17,150				17,150
Vornado Realty Trust \| Due from joint ventures \| 280 Park Avenue
General information on each joint venture
Ownership Interest		50.00%				50.00%
Economic Interest (as a percent)		50.00%				50.00%
Approximate Square Feet		1,219,158				1,219,158
Wharton Properties \| Due from joint ventures \| 1552 Broadway
General information on each joint venture
Ownership Interest		50.00%				50.00%
Economic Interest (as a percent)		50.00%				50.00%
Approximate Square Feet		57,718				57,718
Wharton Properties \| Due from joint ventures \| 650 Fifth Avenue
General information on each joint venture
Ownership Interest		50.00%				50.00%
Economic Interest (as a percent)		50.00%				50.00%
Approximate Square Feet		69,214				69,214
Canadian Pension Plan Investment Board \| Due from joint ventures \| 10 East 53rd Street
General information on each joint venture
Ownership Interest		55.00%				55.00%
Economic Interest (as a percent)		55.00%				55.00%
Approximate Square Feet		354,300				354,300
PGIM Real Estate \| Due from joint ventures \| 11 Madison Avenue
General information on each joint venture
Ownership Interest		60.00%				60.00%
Economic Interest (as a percent)		60.00%				60.00%
Approximate Square Feet		2,314,000				2,314,000
National Pension Service of Korea / Hines Interest LP \| Due from joint ventures \| One Vanderbilt Avenue
General information on each joint venture
Ownership Interest		71.01%				71.01%
Economic Interest (as a percent)		71.01%				71.01%
Approximate Square Feet		1,657,198				1,657,198
RXR Realty / New York REIT \| Due from joint ventures \| Worldwide Plaza (4)
General information on each joint venture
Ownership Interest		24.95%				24.95%
Economic Interest (as a percent)		24.95%				24.95%
Approximate Square Feet		2,048,725				2,048,725
Allianz Real Estate of America \| Due from joint ventures \| 1515 Broadway
General information on each joint venture
Ownership Interest		56.87%				56.87%
Economic Interest (as a percent)		56.87%				56.87%
Approximate Square Feet		1,750,000				1,750,000
Israeli Institutional Investor \| Due from joint ventures \| 2 Herald Square
General information on each joint venture
Ownership Interest		51.00%				51.00%
Economic Interest (as a percent)		51.00%				51.00%
Approximate Square Feet		369,000				369,000
A fund managed by Meritz Alternative Investment Management \| Due from joint ventures \| 15 Beekman
General information on each joint venture
Ownership Interest		20.00%				20.00%
Economic Interest (as a percent)		20.00%				20.00%
Approximate Square Feet		221,884				221,884
A fund managed by Meritz Alternative Investment Management \| Due from joint ventures \| 220 East 42nd Street
General information on each joint venture
Ownership Interest		51.00%				51.00%
Economic Interest (as a percent)		51.00%				51.00%
Approximate Square Feet		1,135,000				1,135,000
Wells Fargo \| Due from joint ventures \| 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		12,946				12,946
National Pension Service of Korea / Hines Interest LP / International Investor \| One Madison Avenue
General information on each joint venture
Ownership percentage deconsolidated									50.50%
Investment fair value adjustment \| $									$ 187,500,000
Investment in joint venture aggregate maximum ownership percentage								25.00%
National Pension Service of Korea / Hines Interest LP / International Investor \| Due from joint ventures \| One Madison Avenue
General information on each joint venture
Ownership Interest		25.50%				25.50%
Economic Interest (as a percent)		25.50%				25.50%
Approximate Square Feet		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 \| Due from joint ventures \| 450 Park Avenue
General information on each joint venture
Ownership Interest		50.10%				50.10%
Economic Interest (as a percent)		25.10%				25.10%
Approximate Square Feet		337,000				337,000
Investment in joint venture, ownership percentage		25.10%				25.10%
RXR Realty led investment group \| Due from joint ventures \| 5 Times Square (4)
General information on each joint venture
Ownership Interest		31.55%				31.55%
Economic Interest (as a percent)		31.55%				31.55%
Approximate Square Feet		1,131,735				1,131,735
U.S. Affiliate of Mori Trust Co., Ltd \| Due from joint ventures \| 245 Park Avenue
General information on each joint venture
Ownership Interest		50.10%				50.10%
Economic Interest (as a percent)		50.10%				50.10%
Approximate Square Feet		1,782,793				1,782,793
Private Investor \| Due from joint ventures \| Madison Ave, 625
General information on each joint venture
Ownership Interest			90.43%

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

12 Months Ended

Dec. 31, 2023

Noncontrolling Interest [Abstract]

Schedule of noncontrolling interest

Below is a summary of the activity relating to the noncontrolling interests in the Operating Partnership for the years ended December 31, 2023 and 2022 (in thousands):


	December 31, 2023		December 31, 2022
Balance at beginning of period	$	269,993	$	344,252
Distributions	(14,779)		(16,272)
Issuance of common units	25,365		22,855
Redemption and conversion of common units	(18,589)		(40,901)
Net loss	(37,465)		(5,794)
Accumulated other comprehensive income allocation	(1,960)		5,827
Fair value adjustment	15,486		(39,974)
Balance at end of period	$	238,051	$	269,993

Schedule of preferred unit activity

Below is a summary of the preferred units of limited partnership interest in the Operating Partnership as of December 31, 2023:


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)	5.00	%	109,161	109,161	109,161	$	50.0000	$	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 convertible on a one-for-one basis, into the Series B Preferred Units of limited partnership interest, or the Subsidiary Series B Preferred Units. The Subsidiary Series B Preferred Units can be converted at any time, after July 15, 2024 at the option of the unitholder, into a number of common stock equal to 6.71348 shares of common stock for each Subsidiary Series B Preferred Unit. As such, no Subsidiary Series B Preferred Units have been issued as of December 31, 2023.

(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 years ended December 31, 2023 and 2022 (in thousands):


	December 31, 2023		December 31, 2022
Balance at beginning of period	$	177,943	$	196,075
Issuance of preferred units	—		—
Redemption of preferred units	(11,700)		(17,967)
Dividends paid on preferred units	(6,271)		(6,198)
Accrued dividends on preferred units	6,529		6,033
Balance at end of period	$	166,501	$	177,943

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2023
Auditor [Line Items]
Auditor Firm ID	42
Auditor Name	Ernst & Young LLP
Auditor Location	New York, New York
SL Green Operating Partnership
Auditor [Line Items]
Auditor Firm ID	42
Auditor Name	Ernst & Young LLP
Auditor Location	New York, New York

Partners' Capital of the Operating Partnership - EPS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Numerator
Less: distributed earnings allocated to participating securities	$ (2,655)	$ (2,219)	$ (2,398)
Less: undistributed earnings allocated to participating securities	0	0	(192)
Net (loss) income attributable to SL Green common stockholders (numerator for basic earnings per share)	(582,164)	(95,243)	432,214
Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares	$ 0	$ 0	$ 2,039
Denominator
Diluted weighted average common stock outstanding (in shares)	67,972,000	67,929,000	70,769,000
Common stock shares excluded from the diluted shares outstanding (in shares)	1,273,417	1,682,236	948,017
SL Green Operating Partnership
Numerator
Net (loss) income attributable to SLGOP common unitholders	$ (616,974)	$ (98,818)	$ 460,261
Less: distributed earnings allocated to participating securities	(2,655)	(2,219)	(2,398)
Less: undistributed earnings allocated to participating securities	0	0	(192)
Net (loss) income attributable to SL Green common stockholders (numerator for basic earnings per share)	(619,629)	(101,037)	457,671
Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares	0	0	2,590
(Loss) income attributable to SLGOP common unitholders	$ (619,629)	$ (101,037)	$ 460,261
Denominator
Basic weighted average common units outstanding (in shares)	67,972,000	67,929,000	69,667,000
Stock-based compensation plans (in shares)	0	0	765,000
Contingently issuable units (in shares)	0	0	337,000
Diluted weighted average common stock outstanding (in shares)	67,972,000	67,929,000	70,769,000

Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

Schedule of contributions made to multi-employer plans

Contributions we made to the multi-employer plans for the years ended December 31, 2023, 2022 and 2021 are included in the table below (in thousands):


	Year Ended December 31,
Benefit Plan	2023		2022		2021
Pension Plan	$	2,111	$	1,952	$	1,994
Health Plan	7,191		6,386		6,333
Other plans	789		807		849
Total plan contributions	$	10,091	$	9,145	$	9,176

- Definition

Tabular disclosure of information about multiemployer plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480547/715-80-55-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-5

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-5

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-5

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (e)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-5

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (e)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-5

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-5

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-5

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-9

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-9

+ Details

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Legal Proceedings

As of December 31, 2023, 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.

Employment Agreements

We have entered into employment agreements with certain executives, which expire between January 2025 and January 2026. The minimum cash-based compensation associated with these employment agreements, which is comprised only of base salary, totals $2.4 million for 2024.

Insurance

We maintain “all-risk” property and rental value coverage (including coverage regarding the perils of flood, earthquake and terrorism, excluding nuclear, biological, chemical, and radiological terrorism ("NBCR"), within two property insurance programs and liability insurance. Separate property and liability coverage may be purchased on a stand-alone basis for certain assets, such as development projects. Additionally, one of our captive insurance companies, Belmont Insurance Company, or Belmont, provides coverage for NBCR terrorist acts above a specified trigger. Belmont's retention is reinsured by our other captive insurance company, Ticonderoga Insurance Company ("Ticonderoga"). If Belmont or Ticonderoga are required to pay a claim under our insurance policies, we would ultimately record the loss to the extent of required payments. However, there is no assurance that in the future we will be able to procure coverage at a reasonable cost. Further, if we experience losses that are uninsured or that exceed policy limits, we could lose the capital invested in the damaged properties as well as the anticipated future cash flows from those properties. Additionally, our debt instruments contain customary covenants requiring us to maintain insurance and we could default under our debt instruments if the cost and/or availability of certain types of insurance make it impractical or impossible to comply with such covenants relating to insurance. Belmont and Ticonderoga provide coverage solely on properties owned by the Company or its affiliates.

Furthermore, with respect to certain of our properties, including properties held by joint ventures or subject to triple net leases, insurance coverage is obtained by a third-party and we do not control the coverage. While we may have agreements with such third parties to maintain adequate coverage and we monitor these policies, such coverage ultimately may not be maintained or adequately cover our risk of loss.

Belmont had loss reserves of $3.3 million and $3.1 million as of December 31, 2023 and 2022, respectively. Ticonderoga had no loss reserves as of December 31, 2023 and 2022.

Lease Arrangements

We are a tenant under leases for certain properties, including ground leases. These leases have expirations from 2033 to 2119, or 2043 to 2119 as fully extended. Certain leases offer extension options which we assess against relevant economic factors to determine whether we are reasonably certain of exercising or not exercising the option. Lease payments associated with renewal periods that we are reasonably certain will be exercised, if any, are included in the measurement of the corresponding lease liability and right of use asset.

Certain of our leases are subject to rent resets, generally based on a percentage of the then fair market value, a fixed amount, or a percentage of the preceding rent at specified future dates. Rent resets will be recognized in the periods in which they are incurred. Additionally, certain of our leases are subject to percentage rent arrangements based on thresholds established in the lease agreement, such as percentage of sales at the property. Percentage rents will be recognized in the periods in which they are incurred.

The table below summarizes our current lease arrangements as of December 31, 2023:


Property (1)	Year of Current Expiration	Year of Final Expiration (2)
711 Third Avenue (3)	2033	2083
1185 Avenue of the Americas	2043	2043
SL Green Headquarters at One Vanderbilt Avenue (4)	2043	2048
420 Lexington Avenue	2050	2080
SUMMIT One Vanderbilt	2058	2070
15 Beekman (5)(6)	2119	2119

(1)All leases are classified as operating leases unless otherwise specified.

(2)Reflects exercise of all available extension options.

(3)The Company owns 50% of the fee interest.

(4)In March 2021, the Company commenced its lease for its corporate headquarters at One Vanderbilt Avenue. See note 10, "Related Party Transactions."

(5)The Company has an option to purchase the ground lease for a fixed price on a specific date. The lease is classified as a financing lease.

(6)In August 2020, the Company entered into a long-term sublease with an unconsolidated joint venture as part of the capitalization of the 15 Beekman development project. See Note 6, "Investments in Unconsolidated Joint Ventures."

The following is a schedule of future minimum lease payments as evaluated in accordance with ASC 842 for our financing leases and operating leases with initial terms in excess of one year as of December 31, 2023 (in thousands):


	Financing leases		Operating leases
2024	$	3,180	$	53,455
2025	3,228		53,595
2026	3,276		53,734
2027	3,325		53,746
2028	3,375		54,211
Thereafter	196,794		1,208,864
Total minimum lease payments	$	213,178	$	1,477,605
Amount representing interest	(107,647)		—
Amount discounted using incremental borrowing rate	—		(649,913)
Total lease liabilities excluding liabilities related to assets held for sale	$	105,531	$	827,692

Total lease liabilities	$	105,531	$	827,692

The following table provides lease cost information for the Company's operating leases for the years ended December 31, 2023, 2022 and 2021 (in thousands):


	Year Ended December 31,
Operating Lease Costs	2023		2022		2021
Operating lease costs before capitalized operating lease costs	$	29,637	$	33,773	$	30,270
Operating lease costs capitalized	(2,345)		(6,830)		(3,716)
Operating lease costs, net (1)	$	27,292	$	26,943	$	26,554

(1)This amount is included in Operating lease rent in our consolidated statements of operations.

The following table provides lease cost information for the Company's financing leases for the years ended December 31, 2023, 2022 and 2021 (in thousands):


	Year Ended December 31,
Financing Lease Costs	2023		2022		2021
Interest on financing leases before capitalized interest	$	4,446	$	4,555	$	5,448
Interest on financing leases capitalized	—		—		—
Interest on financing leases, net (1)	4,446		4,555		5,448
Amortization of right-of-use assets (2)	—		—		660


Financing lease costs, net	$	4,446	$	4,555	$	6,108

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

(2)These amounts are included in Depreciation and amortization in our consolidated statements of operations.

As of December 31, 2023, the weighted-average discount rate used to calculate the lease liabilities was 4.46%. As of December 31, 2023, the weighted-average remaining lease term was 28 years, inclusive of purchase options expected to be exercised.

Property Acquisitions - Schedule of Properties Acquired in 2021 (Details) $ in Millions	Dec. 31, 2023 ft²	Dec. 31, 2021 USD ($) ft²
Business Acquisition [Line Items]
Approximate Square Feet	29,695,841
885 Third Avenue
Business Acquisition [Line Items]
Approximate Square Feet		625,000
Gross Asset Valuation \| $		$ 387.9
461 Fifth Avenue
Business Acquisition [Line Items]
Approximate Square Feet		200,000
Gross Asset Valuation \| $		$ 28.0
1591-1597 Broadway
Business Acquisition [Line Items]
Approximate Square Feet		7,684
Gross Asset Valuation \| $		$ 121.0
690 Madison Avenue
Business Acquisition [Line Items]
Approximate Square Feet		7,848
Gross Asset Valuation \| $		$ 72.2

Partners' Capital of the Operating Partnership (Tables)

12 Months Ended

Dec. 31, 2023

Equity [Abstract]

Schedule of calculation of numerator and denominator in earnings per unit

The Operating Partnership's earnings per unit for the years ended December 31, 2023, 2022, and 2021 respectively are computed as follows (in thousands):


	Year Ended December 31,
Numerator	2023		2022		2021
Basic Earnings:
Net (loss) income attributable to SLGOP common unitholders (numerator for diluted earnings per unit)	$	(616,974)	$	(98,818)	$	460,261
Less: distributed earnings allocated to participating securities	(2,655)		(2,219)		(2,398)
Less: undistributed earnings allocated to participating securities	—		—		(192)
Net (loss) income attributable to SLGOP common unitholders (numerator for basic earnings per unit)	$	(619,629)	$	(101,037)	$	457,671
Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares	—		—		2,590

(Loss) income attributable to SLGOP common unitholders	$	(619,629)	$	(101,037)	$	460,261


	Year Ended December 31,
Denominator	2023	2022	2021
Basic units:
Weighted average common units outstanding	67,972	67,929	69,667
Effect of Dilutive Securities:
Stock-based compensation plans	—	—	765
Contingently issuable units	—	—	337
Diluted weighted average common units outstanding	67,972	67,929	70,769

Fair Value Measurements

12 Months Ended

Dec. 31, 2023

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.

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 December 31, 2023 and 2022 (in thousands):


	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	$	—


	December 31, 2022
	Total		Level 1		Level 2		Level 3
Assets:
Marketable securities available-for-sale	$	11,240	$	—	$	11,240	$	—
Interest rate cap and swap agreements (included in Other assets)	$	57,660	$	—	$	57,660	$	—
Liabilities:
Interest rate cap and swap agreements (included in Other liabilities)	$	10,142	$	—	$	10,142	$	—

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 June 2023, the Company sold a 49.9% interest in its 245 Park Avenue investment, which resulted in the Company no longer retaining a controlling interest in the entity, as defined in ASC 810, and deconsolidation of the 50.1% interest we retained. We recorded our investment at fair value which resulted in the recognition of a fair value adjustment of ($17.0 million) during the year ended December 31, 2023. The fair value of our investment was determined by the terms of the joint venture agreement.

In September 2022, the Company recorded at fair value the assets acquired and liabilities assumed at 245 Park Avenue. 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 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 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 December 31, 2023 and December 31, 2022 (in thousands):


	December 31, 2023				December 31, 2022
	Carrying Value (1)		Fair Value		Carrying Value (1)		Fair Value

Debt and preferred equity investments	$	346,745	(2)		$	623,280	(2)

Fixed rate debt	$	3,237,386	$	3,184,338	$	5,015,814	$	4,784,691
Variable rate debt (3)	270,000		268,787		520,148		519,669
Total debt	$	3,507,386	$	3,453,125	$	5,535,962	$	5,304,360

(1)Amounts exclude net deferred financing costs.

(2)As of December 31, 2023, debt and preferred equity investments had an estimated fair value of approximately $0.3 billion. As of December 31, 2022, debt and preferred equity investments had an estimated fair value ranging between $0.6 billion and $0.6 billion.

(3)As of December 31, 2023, variable rate debt with a carrying value of $110.0 million and fair value of $108.6 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 December 31, 2023 and 2022. 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 + Details

Investments in Unconsolidated Joint Ventures (Tables)

12 Months Ended

Dec. 31, 2023

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 December 31, 2023:


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
717 Fifth Avenue (2) (3)	Wharton Properties / Private Investor	10.92%	10.92%	119,500
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) (4)	Wharton Properties	50.00%	50.00%	57,718
10 East 53rd Street	Canadian Pension Plan Investment Board	55.00%	55.00%	354,300
650 Fifth Avenue (2) (5)	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) (6)	Israeli Institutional Investor	51.00%	51.00%	369,000
115 Spring Street (2)	Private Investor	51.00%	51.00%	5,218
15 Beekman (7)	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 (8)	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 (9)	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 (10)	U.S. Affiliate of Mori Trust Co., Ltd	50.10%	50.10%	1,782,793
625 Madison Avenue (11)	Private Investor	90.43%	90.43%	563,000

(1)Ownership interest and economic interest represent the Company's interests in the joint venture as of December 31, 2023. 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)In January 2024, together with its joint venture partner, the Company closed on the sale of the retail condominium at 717 Fifth Avenue for total consideration of $963.0 million.

(4)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. In December 2023, following an assessment of the investment for recoverability, the Company recorded a charge of $8.1 million, which is included in Depreciable real estate reserves and impairments in the consolidated statements of operations.

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

(6)In December 2023, following an assessment of the property and the investment for recoverability, the Company recorded a charge of $101.7 million, which is included in Depreciable real estate reserves and impairments in the consolidated statements of operations. 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%. In addition, the joint venture entered into an agreement to satisfy the existing $182.5 million mortgage on the property for a net payment of $7.0 million, which closed in February 2024.

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

(8)In 2020, the Company admitted partners to the One Madison Avenue development project, which resulted in the Company no longer retaining a controlling interest in the entity, as defined in ASC 810, and deconsolidation of our remaining 50.5% interest. We recorded our investment at fair value, which resulted in the recognition of a fair value adjustment of $187.5 million. The fair value of our investment was determined by the terms of the joint venture agreement governing the capitalization of the project. 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 December 31, 2023 and 2022.

(9)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.

(10)In June 2023, the Company sold a 49.9% interest, which resulted in the Company no longer retaining a controlling interest in the entity, as defined in ASC 810, and deconsolidation of the 50.1% interest we retained. We recorded our investment at fair value which resulted in the recognition of a fair value adjustment of ($17.0 million) during the year ended December 31, 2023. The fair value of our investment was determined by the terms of the joint venture agreement.

(11)In September 2023, following a UCC foreclosure, the Company converted its previous mezzanine debt investments in the fee interest to a 90.43% ownership interest. See Note 5, "Debt and Preferred Equity Investments." In December 2023, together with its joint venture, the Company entered into a contract to sell the fee ownership in the property. In connection with this contract, the Company recorded a charge of $23.1 million, which is included in Depreciable real estate reserves and impairments in the consolidated statements of operations. This transaction is expected to close in the first quarter of 2024.

The following table summarizes the investments in unconsolidated joint ventures sold during the years ended December 31, 2023, 2022, and 2021:


Property	Ownership Interest Sold	Disposition Date	Gross Asset Valuation (in millions)		(Loss) Gain on Sale (in millions) (1) (2)
21 East 66th Street	32.28%	December 2023	$	40.6	$	(12.7)
121 Greene Street	50.00%	February 2023	14.0		(0.3)
Stonehenge Portfolio	Various	April 2022	1.0		—
400 East 57th Street (3)	41.00%	September 2021	133.5		(1.0)
605 West 42nd Street - Sky	20.00%	June 2021	858.1		8.9
55 West 46th Street - Tower 46	25.00%	March 2021	275.0		(15.2)
885 Third Avenue (4)	N/A	January 2021	N/A		N/A

(1)Represents the Company's share of the gain or loss

(2)For the years ended December 31, 2023 and December 31, 2021, the (losses) gains on sale are net of $2.0 million and $1.4 million, respectively, of employee compensation accrued in connection with the realization of the investment dispositions. There was no amount accrued for employee compensation in the year ended December 31, 2022. Additionally, amounts do not include adjustments for expenses recorded in subsequent periods.

(3)In connection with our agreement to sell the property in April 2021, we recorded a charge of $5.7 million, which is included in Depreciable real estate reserves and impairments in the consolidated statements of operations.

(4)In January 2021, pursuant to the partnership documents, certain participating rights of the common member expired. As a result, it was determined that we are the primary beneficiary of the VIE and the investment was consolidated in our financial statements. See Note 3, "Property Acquisitions."

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 December 31, 2023 and 2022, respectively, are as follows (dollars in thousands):


							Principal Outstanding				Principal Outstanding
	Economic		Current Maturity	Final Maturity	Interest		December 31, 2023				December 31, 2022
Property	Interest (1)		Date	Date (2)	Rate (3)		Gross		SLG Share		Gross		SLG Share
Fixed Rate Debt:

717 Fifth Avenue (4)(5)	10.92	%	July 2022 (5)	July 2022 (5)		5.02%	$	655,328	$	71,536	$	655,328	$	71,536
650 Fifth Avenue (4)	50.00	%	October 2023 (6)	January 2024 (6)		5.45%	65,000		32,500		65,000		32,500
220 East 42nd Street	51.00	%	June 2024	June 2025		5.86%	505,412		257,760		510,000		260,100
5 Times Square (4)	31.55	%	September 2024	September 2026		7.13%	477,783		150,740		400,000		126,200
10 East 53rd Street	55.00	%	February 2025	February 2025		5.45%	220,000		121,000		220,000		121,000
1515 Broadway	56.87	%	March 2025	March 2025		3.93%	762,002		433,344		782,321		444,898
115 Spring Street (4)	51.00	%	March 2025	March 2025		5.50%	65,550		33,431		—		—
450 Park Avenue	25.10	%	June 2025	June 2027		6.10%	271,394		68,120		267,000		67,017
11 Madison Avenue	60.00	%	September 2025	September 2025		3.84%	1,400,000		840,000		1,400,000		840,000
One Madison Avenue (7)	25.50	%	November 2025	November 2026		3.59%	733,103		186,941		467,008		119,087
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
625 Madison Avenue (8)	90.43	%	December 2026	December 2026		5.11%	199,987		180,848		—		—
245 Park Avenue	50.10	%	June 2027	June 2027		4.30%	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
One Vanderbilt Avenue	71.01	%	July 2031	July 2031		2.95%	3,000,000		2,130,300		3,000,000		2,130,300
280 Park Avenue							—		—		1,200,000		600,000
21 East 66th Street							—		—		12,000		3,874
Total fixed rate debt							$	12,000,559	$	6,053,808	$	10,855,657	$	5,478,032

Floating Rate Debt:
11 West 34th Street (4)	30.00	%	February 2023 (9)	February 2023 (9)	L+	1.45%	$	23,000	$	6,900	$	23,000	$	6,900
650 Fifth Avenue (4)	50.00	%	October 2023 (6)	January 2024 (6)	S+	2.25%	210,000		105,000		210,000		105,000
2 Herald Square (4)(10)	51.00	%	November 2023(10)	November 2023(10)	S+	2.06%	182,500		93,075		182,500		93,075
100 Park Avenue	49.90	%	January 2024 (11)	December 2025	S+	2.36%	360,000		179,640		360,000		179,640
15 Beekman (12)	20.00	%	January 2024 (13)	July 2025	S+	1.61%	124,137		24,827		86,738		17,348
1552 Broadway (4)	50.00	%	February 2024	February 2024	S+	2.75%	193,133		96,567		193,132		96,566
5 Times Square (4)	31.55	%	September 2024	September 2026	S+	5.65%	610,010		192,458		495,924		156,464
280 Park Avenue	50.00	%	September 2024	September 2024	S+	2.03%	1,200,000		600,000		—		—
21 East 66th Street							—		—		586		188
115 Spring Street							—		—		65,550		33,431
121 Greene Street							—		—		12,550		6,275
Total floating rate debt							$	2,902,780	$	1,298,467	$	1,629,980	$	694,887
Total joint venture mortgages and other loans payable							$	14,903,339	$	7,352,275	$	12,485,637	$	6,172,919
Deferred financing costs, net							(104,062)		(54,865)		(136,683)		(66,910)
Total joint venture mortgages and other loans payable, net							$	14,799,277	$	7,297,410	$	12,348,954	$	6,106,009

(1)Economic interest represents the Company's interests in the joint venture as of December 31, 2023. 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 options. The ability to exercise extension options may be subject to certain conditions, including meeting tests based on the operating performance of the property.

(3)Interest rates as of December 31, 2023, taking into account interest rate hedges in effect during the period. Floating rate debt is presented with the stated spread over Term SOFR ("S").

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

(5)The asset was sold and associated debt repaid in January 2024.

(6)In January 2024, the maturity date of the loan was extended by two months to March 2024.

(7)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. In July 2023, the facility was modified, which will allow the partnership to utilize the final tranche of the facility for an expanded range of uses, including additional amenities funded by construction cost savings and for hedging activities in contemplation of a permanent financing.

(8)Represents $168.9 million of loan principal and $31.1 million of accrued interest.

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

(10)The Company closed on the acquisition of additional interests in the joint venture in January 2024, which increased the Company's interest to 95%. In addition, the joint venture entered into an agreement to satisfy the existing mortgage for a net payment of $7.0 million, which closed in February 2024.

(11)The Company is in discussions with the lender to exercise the available extension option.

(12)This loan is a $125.0 million construction facility. Advances under the loan are subject to costs incurred.

(13)In January 2024, the maturity date of the loan was extended to July 2024.

Schedule of Combined Balance Sheets for the Unconsolidated Joint Ventures

The combined balance sheets for the unconsolidated joint ventures, as of December 31, 2023 and 2022, are as follows (in thousands):


	December 31, 2023		December 31, 2022
Assets (1)
Commercial real estate property, net	$	18,467,340	$	15,989,642
Cash and restricted cash	656,038		709,299
Tenant and other receivables, related party receivables, and deferred rents receivable	673,532		601,552

Other assets	2,584,765		2,551,426
Total assets	$	22,381,675	$	19,851,919
Liabilities and equity (1)
Mortgages and other loans payable, net	$	14,799,277	$	12,348,954
Deferred revenue	1,108,180		1,077,901
Lease liabilities	990,276		1,000,356
Other liabilities	447,705		456,537
Equity	5,036,237		4,968,171
Total liabilities and equity	$	22,381,675	$	19,851,919
Company's investments in unconsolidated joint ventures	$	2,983,313	$	3,190,137

(1)As of December 31, 2023, $545.6 million of net unamortized basis differences between the amount at which our investments are carried 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 years ended December 31, 2023, 2022, and 2021 are as follows (unaudited, in thousands):


	Year Ended December 31,
	2023		2022		2021
Total revenues	$	1,525,044	$	1,339,364	$	1,228,364
Operating expenses	253,630		240,002		203,332
Real estate taxes	287,462		252,806		225,104
Operating lease rent	29,048		26,152		22,576
Interest expense, net of interest income	574,032		431,865		342,910
Amortization of deferred financing costs	28,157		27,754		31,423

Depreciation and amortization	516,466		465,100		484,130
Total expenses	$	1,688,795	$	1,443,679	$	1,309,475
Loss on early extinguishment of debt	—		(467)		(2,017)
Net loss before (loss) gain on sale	$	(163,751)	$	(104,782)	$	(83,128)
Company's equity in net loss from unconsolidated joint ventures	$	(76,509)	$	(57,958)	$	(55,402)

Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (599,337)	$ (76,303)	$ 480,632
Other comprehensive (loss) income:
(Decrease) increase in unrealized value of derivative instruments, including SL Green's share of joint venture derivative instruments	(32,437)	103,629	21,427
(Decrease) increase in unrealized value of marketable securities	(1,650)	(1,440)	104
Other comprehensive (loss) income	(34,087)	102,189	21,531
Comprehensive (loss) income	(633,424)	25,886	502,163
Net loss (income) attributable to noncontrolling interests and preferred units distributions	34,778	(1,771)	(30,878)
Other comprehensive loss (income) attributable to noncontrolling interests	1,960	(5,827)	(1,042)
Comprehensive income attributable to SL Green/SLGOP	$ (596,686)	$ 18,288	$ 470,243

Property Acquisitions (Tables)

12 Months Ended

Dec. 31, 2023

Business Combination and Asset Acquisition [Abstract]

Schedule of Properties Acquired

The following table summarizes the properties acquired during the year ended December 31, 2022:

Property

Acquisition Date

Property Type

Approximate Square Feet

Gross Asset Valuation
(in millions)

245 Park Avenue (1)

September 2022

Fee Interest

1,782,793

1,960.0

(1)On October 31, 2021, HNA, through an affiliated entity, filed for Chapter 11 bankruptcy protection on account of its investment in 245 Park Avenue, together with another asset in Chicago. On July 8, 2022, certain of the debtors and affiliates of SL Green entered into a Plan Sponsorship and Investment Agreement (the "Plan"). Since the debtors did not receive any qualifying bids for the property and the Plan was confirmed, SL Green acquired full ownership and control of the property in September 2022, at which time our outstanding preferred equity and accrued interest balance were credited to our equity investment in the property. We recorded the assets acquired and liabilities assumed at fair value. See Note 16, "Fair Value Measurements."

2021 Acquisitions

The following table summarizes the properties acquired during the year ended December 31, 2021:

Property

Acquisition Date

Property Type

Approximate Square Feet

Gross Asset Valuation
(in millions)

885 Third Avenue (1)

January 2021

Fee Interest

625,000

387.9

461 Fifth Avenue (2)

June 2021

Fee Interest

200,000

28.0

1591-1597 Broadway

September 2021

Fee Interest

7,684

121.0

690 Madison Avenue (3)

September 2021

Fee Interest

7,848

72.2

(1)In January 2021, pursuant to the partnership documents of our 885 Third Avenue investment, certain participating rights of the common member expired. As a result, it was determined that this investment is a VIE in which we are 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. Prior to January 2021, the investment was accounted for under the equity method. See Note 6, "Investments in Unconsolidated Joint Ventures."

(2)In April 2021, the Company exercised its option to acquire the fee interest in the property from the ground lessor and the Company acquired the fee interest in June 2021. The Company held the leasehold interest in the property prior to exercising its option.

(3)In September 2021, the Company was the successful bidder for the fee interest in 690 Madison Avenue at the foreclosure of the asset. The property previously served as collateral for a debt and preferred equity investment. We recorded the assets acquired and liabilities assumed at fair value.

Investments in Unconsolidated Joint Ventures

12 Months Ended

Dec. 31, 2023

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 December 31, 2023, the book value of these investments was $3.0 billion, net of investments with negative book values totaling $149.1 million for which we have an implicit commitment to fund future capital needs.

As of December 31, 2023, 800 Third Avenue and 625 Madison Avenue are VIEs in which we are not the primary beneficiary. As of December 31, 2022, 800 Third Avenue and 21 East 66th Street are VIEs in which we are not the primary beneficiary. Our net equity investment in these VIEs was $437.9 million as of December 31, 2023 and $86.2 million as of December 31, 2022. 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 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 December 31, 2023:


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
717 Fifth Avenue (2) (3)	Wharton Properties / Private Investor	10.92%	10.92%	119,500
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) (4)	Wharton Properties	50.00%	50.00%	57,718
10 East 53rd Street	Canadian Pension Plan Investment Board	55.00%	55.00%	354,300
650 Fifth Avenue (2) (5)	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) (6)	Israeli Institutional Investor	51.00%	51.00%	369,000
115 Spring Street (2)	Private Investor	51.00%	51.00%	5,218
15 Beekman (7)	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 (8)	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 (9)	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 (10)	U.S. Affiliate of Mori Trust Co., Ltd	50.10%	50.10%	1,782,793
625 Madison Avenue (11)	Private Investor	90.43%	90.43%	563,000

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

(3)In January 2024, together with its joint venture partner, the Company closed on the sale of the retail condominium at 717 Fifth Avenue for total consideration of $963.0 million.

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

(7)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 years ended December 31, 2023, 2022, and 2021:


Property	Ownership Interest Sold	Disposition Date	Gross Asset Valuation (in millions)		(Loss) Gain on Sale (in millions) (1) (2)
21 East 66th Street	32.28%	December 2023	$	40.6	$	(12.7)
121 Greene Street	50.00%	February 2023	14.0		(0.3)
Stonehenge Portfolio	Various	April 2022	1.0		—
400 East 57th Street (3)	41.00%	September 2021	133.5		(1.0)
605 West 42nd Street - Sky	20.00%	June 2021	858.1		8.9
55 West 46th Street - Tower 46	25.00%	March 2021	275.0		(15.2)
885 Third Avenue (4)	N/A	January 2021	N/A		N/A

(1)Represents the Company's share of the gain or loss

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 December 31, 2023 and 2022, respectively, are as follows (dollars in thousands):


							Principal Outstanding				Principal Outstanding
	Economic		Current Maturity	Final Maturity	Interest		December 31, 2023				December 31, 2022
Property	Interest (1)		Date	Date (2)	Rate (3)		Gross		SLG Share		Gross		SLG Share
Fixed Rate Debt:

717 Fifth Avenue (4)(5)	10.92	%	July 2022 (5)	July 2022 (5)		5.02%	$	655,328	$	71,536	$	655,328	$	71,536
650 Fifth Avenue (4)	50.00	%	October 2023 (6)	January 2024 (6)		5.45%	65,000		32,500		65,000		32,500
220 East 42nd Street	51.00	%	June 2024	June 2025		5.86%	505,412		257,760		510,000		260,100
5 Times Square (4)	31.55	%	September 2024	September 2026		7.13%	477,783		150,740		400,000		126,200
10 East 53rd Street	55.00	%	February 2025	February 2025		5.45%	220,000		121,000		220,000		121,000
1515 Broadway	56.87	%	March 2025	March 2025		3.93%	762,002		433,344		782,321		444,898
115 Spring Street (4)	51.00	%	March 2025	March 2025		5.50%	65,550		33,431		—		—
450 Park Avenue	25.10	%	June 2025	June 2027		6.10%	271,394		68,120		267,000		67,017
11 Madison Avenue	60.00	%	September 2025	September 2025		3.84%	1,400,000		840,000		1,400,000		840,000
One Madison Avenue (7)	25.50	%	November 2025	November 2026		3.59%	733,103		186,941		467,008		119,087
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
625 Madison Avenue (8)	90.43	%	December 2026	December 2026		5.11%	199,987		180,848		—		—
245 Park Avenue	50.10	%	June 2027	June 2027		4.30%	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
One Vanderbilt Avenue	71.01	%	July 2031	July 2031		2.95%	3,000,000		2,130,300		3,000,000		2,130,300
280 Park Avenue							—		—		1,200,000		600,000
21 East 66th Street							—		—		12,000		3,874
Total fixed rate debt							$	12,000,559	$	6,053,808	$	10,855,657	$	5,478,032

Floating Rate Debt:
11 West 34th Street (4)	30.00	%	February 2023 (9)	February 2023 (9)	L+	1.45%	$	23,000	$	6,900	$	23,000	$	6,900
650 Fifth Avenue (4)	50.00	%	October 2023 (6)	January 2024 (6)	S+	2.25%	210,000		105,000		210,000		105,000
2 Herald Square (4)(10)	51.00	%	November 2023(10)	November 2023(10)	S+	2.06%	182,500		93,075		182,500		93,075
100 Park Avenue	49.90	%	January 2024 (11)	December 2025	S+	2.36%	360,000		179,640		360,000		179,640
15 Beekman (12)	20.00	%	January 2024 (13)	July 2025	S+	1.61%	124,137		24,827		86,738		17,348
1552 Broadway (4)	50.00	%	February 2024	February 2024	S+	2.75%	193,133		96,567		193,132		96,566
5 Times Square (4)	31.55	%	September 2024	September 2026	S+	5.65%	610,010		192,458		495,924		156,464
280 Park Avenue	50.00	%	September 2024	September 2024	S+	2.03%	1,200,000		600,000		—		—
21 East 66th Street							—		—		586		188
115 Spring Street							—		—		65,550		33,431
121 Greene Street							—		—		12,550		6,275
Total floating rate debt							$	2,902,780	$	1,298,467	$	1,629,980	$	694,887
Total joint venture mortgages and other loans payable							$	14,903,339	$	7,352,275	$	12,485,637	$	6,172,919
Deferred financing costs, net							(104,062)		(54,865)		(136,683)		(66,910)
Total joint venture mortgages and other loans payable, net							$	14,799,277	$	7,297,410	$	12,348,954	$	6,106,009