Prior Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year Balance at beginning of period Balance at end of period SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate Proceeds from sale of marketable securities Proceeds from Sale of Debt Securities, Available-for-Sale Loan loss reserve activity Financing Receivable, Allowance for Credit Loss [Roll Forward] Number of extension options Debt Instrument, Number of Extension Options Debt Instrument, Number of Extension Options Assumption of mortgage and mezzanine loans Assumption Of Mortgage And Mezzanine Loans Assumption Of Mortgage And Mezzanine Loans Maximum facility capacity Line of Credit Facility, Maximum Borrowing Capacity Debt Investment [Domain] Debt Investment [Domain] Debt Investment [Domain] Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares) Deferred Compensation Plan and Stock Award, Shares Number of shares issued during the period from a Deferred Compensation Plan and Stock Award. Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Related Party Transactions Related Party Transaction [Line Items] Award expiration period (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period Convertible preferred stock, shares issued upon conversion (in shares) Convertible Preferred Stock, Shares Issued upon Conversion Annual award vesting rate, high end of range (as a percent) Share Based Compensation Arrangement by Share Based Payment Award, Award Vesting Rate, High End of Range Represents the low end of the range of annual vesting rates that occurs once performance criteria are reached. Award Type [Domain] Award Type [Domain] Investment, Name [Domain] Investment, Name [Domain] Purchase price and other fair value adjustments Purchase Price, Fair Value Adjustment, Gain (Loss) Purchase Price, Fair Value Adjustment, Gain (Loss) 420 Lexington Ave Lexington Avenue, 420 [Member] Represents the information pertaining to 420 Lexington Avenue, a property owned by the entity. Term Loan Unsecured Term Loans Term Loan [Member] Represents the term loan of the reporting entity. Options exercisable at end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number Deconsolidation of a subsidiary Deconsolidation Of Subsidiary Deconsolidation Of Subsidiary Stockholders' Equity of the Company Partners' Capital of the Operating Partnership Accumulated Other Comprehensive Income Equity [Text Block] Schedule of preferred unit activity Schedule of Preferred Units [Table Text Block] Ownership [Axis] Ownership [Axis] Fixed lease payments Operating Lease, Lease Income, Lease Payments 3 - High Risk Assets - Loss more likely than not Risk Level, High [Member] Deferred rents receivable Deferred Rent Receivables, Net Customer [Axis] Customer [Axis] Mori Trust Co., Ltd Mori Trust Co., Ltd [Member] Mori Trust Co., Ltd Series I Preferred Stock, $0.01 par value, $25.00 liquidation preference, 9,200 issued and outstanding at both September 30, 2023 and December 31, 2022 Preferred Stock, Value, Issued SL Green partners' capital, limited partner common units outstanding (shares) Limited Partnership Units Held by General Partner This element represents Limited Partnership Units Held by General Partner. Lapsed or canceled (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Diluted (loss) earnings per share (in dollars per share) Earnings Per Share, Diluted 2027 Future Amortization of Debt Fifth Full Fiscal Year The amount of amortization of debt expected to be recognized during the fifth full fiscal year following the date of the most recent balance sheet. LTIP units Long Term Incentive Plan Units [Member] LTIP units as awarded by a company to its employees as a form of incentive compensation. Line of Credit Line of Credit [Member] 1 - Low Risk Assets - Low probability of loss Risk Level, Low [Member] Real estate taxes Real Estate Tax Expense Trading Symbol Trading Symbol Letters of credit Letters of Credit Outstanding, Amount Less: accumulated amortization Accumulated Amortization of Deferred Costs The accumulated amortization, as of the reporting date, representing the periodic charge to earnings of deferred costs. Investments in unconsolidated joint ventures Payments to Acquire Equity Method Investments Series K Series K Preferred Stock [Member] Series K Preferred Stock [Member] Cash and restricted cash assumed from acquisition of real estate investment Cash Acquired from Acquisition Conversion Price Per Unit (in dollars per share) Operating Partnership Common Unit Value, Per Share Use for Conversion Represents the common stock value per share which is used for purposes of determining the number of operating partnership common stock issue on conversion of preferred unit. Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Amortization of discount on assumed debt Amortization of Debt Discount (Premium) Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] Term Loan A, Maturity May 2026 Term Loan A, Maturity May 2026 [Member] Term Loan A, Maturity May 2026 [Member] Suburban Suburban [Member] Represents information pertaining to property located in Suburban areas. Debt and Preferred Equity Investments Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Deferred revenue Contract with Customer, Liability Total amortization of debt Future Amortization of Debt The total expected future amortization of debt. Management Service, Base Management Service, Base [Member] Schedule of earnings per share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Stabilization of property, liquidation value, amount monetized Related Party Transaction, Amounts of Transaction Summary of restricted stock Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Significant Accounting Policies Significant Accounting Policies [Text Block] Exercised (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Level 1 Fair Value, Inputs, Level 1 [Member] Carrying Value Reported Value Measurement [Member] Mezzanine Loan Due June 2024 Mezzanine Loan Due June 2024 [Member] Mezzanine Loan Due June 2024 Removal of fully depreciated commercial real estate properties Removal of Fully Depreciated Real Estate Assets Removal of Fully Depreciated Real Estate Assets Other obligations related to secured borrowing Proceeds From Other Obligation Related To Secured Borrowing Proceeds From Other Obligation Related To Secured Borrowing Equity Components [Axis] Equity Components [Axis] Financial Instruments [Domain] Financial Instruments [Domain] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] Preferred equity investment SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] Shares of common stock available for issuance (shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant Investment Type [Axis] Investment Type [Axis] SL Green partner's capital, general partner common units outstanding (shares) General Partners' Capital Account, Units Outstanding 2025 Long-Term Debt, Maturity, Year Two Allowance for loan and lease losses, real estate Balance at beginning of year Balance at end of period Allowance for loan loss Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest Entity Small Business Entity Small Business Basic Shares: Weighted Average Number of Shares Outstanding, Basic [Abstract] Investments [Domain] Investments [Domain] Employee-related liabilities Employee-related Liabilities Deferred Costs Deferred Financing and Leasing Costs Disclosure [Text Block] Costs incurred in connection with financing activities (fees to banks) and costs incurred in connection with leasing activities (fees to real estate brokers), net of amortization. Local Phone Number Local Phone Number Net income (loss) Profit Loss, Less Preferred Distributions The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest, less preferred distributions during the period. 121 Greene Street Greene Street 121 [Member] Greene Street 121 [Member] Other comprehensive income Other Comprehensive Income (Loss), Net of Tax, Less Portion Attributable to Noncontrolling Interest Other Comprehensive Income (Loss), Net of Tax, Less Portion Attributable to Noncontrolling Interest Holiday And Mathias Holiday And Mathias [Member] Holiday And Mathias [Member] 800 Third Avenue Third Avenue, 800 [Member] Represents the information pertaining to 800 Third Avenue, a joint venture property of the entity. Interest Rate Swap Expiring in February 2027, 3 Interest Rate Swap Expiring in February 2027, 3 [Member] Interest Rate Swap Expiring in February 2027, 3 Summary of restricted stock and charges during the period Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] Number of units of operating partnership owned by the noncontrolling interest unit holders (shares) Number of units of operating partnership owned by the noncontrolling interest unit holders (units) Minority Interest Units of Partnership Owned by Noncontrolling Owners Represents the number of partnership units owned by the noncontrolling unit holders. Summary of identified intangible assets (acquired above-market leases and in-place leases) and intangible liabilities (acquired below-market leases) Schedule of Intangible Assets and Liabilities [Table Text Block] Tabular disclosure of the aggregate amount of intangible assets and liabilities. Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Schedule of senior unsecured notes and other related disclosures by scheduled maturity date Schedule of Long-Term Debt Instruments [Table Text Block] 85 Fifth Avenue 85 Fifth Avenue [Member] 85 Fifth Avenue Schedule of general information on joint ventures Equity Method Investments [Table Text Block] Mortgage loan Mortgages [Member] 245 Park Avenue Park Avenue, 245 [Member] Park Avenue, 245 Total revenues Management fees, base revenue Total revenues Revenues Preferred unit distributions as a percentage of common unit distributions Share Based Compensation Arrangement by Share Based Payment Award, Preferred Unit Distributions as a Percentage of Common Unit Distributions Share Based Compensation Arrangement by Share Based Payment Award, Preferred Unit Distributions as a Percentage of Common Unit Distributions Contingently issuable shares (in shares) Incremental Common Shares Attributable to Dilutive Effect of Nonvested Shares with Forfeitable Dividends Award Type [Axis] Award Type [Axis] Common stock shares excluded from the diluted shares outstanding (shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Awards granted (in shares) Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Document Quarterly Report Document Quarterly Report Interest Rate Swap Expiring in May 2027 Interest Rate Swap Expiring in May 2027 [Member] Interest Rate Swap Expiring in May 2027 Cash distributions declared Dividends, Common Stock DRSPP proceeds (in shares) Stock Issued During Period, Shares, Dividend Reinvestment Plan Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Exercise Price [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Exercise Price [Roll Forward] Recognition of right of use assets and related lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Related Party Transactions Related Party Transactions Disclosure [Text Block] Mezzanine Loan Due November 2023 Mezzanine Loan Due November 2023 [Member] Mezzanine Loan Due November 2023 Identified intangible assets (included in other assets): Finitely Lived Intangible Assets [Abstract] -- None. No documentation exists for this element. -- Real Estate [Domain] Real Estate [Domain] Three Residential Units Three Residential Units [Member] Three Residential Units [Member] Net Finite-Lived Intangible Assets, Net Investment in Commercial Real Estate Properties Property, Plant and Equipment [Line Items] Accounting Standards Updates New Accounting Pronouncements, Policy [Policy Text Block] Net loss (income) attributable to noncontrolling interests: Net Income (Loss) Attributable to Noncontrolling Interest [Abstract] Gain (loss) from changes in fair value Gain (Loss) on Sale of Derivatives Average price paid per share (in dollars per share) Shares Acquired, Average Cost Per Share Deferred net losses from terminated hedges Other Comprehensive Income (Loss), Deferred Net Loss from Terminated Hedges Other Comprehensive Income (Loss), Deferred Net Loss from Terminated Hedges Counterparty Name [Domain] Counterparty Name [Domain] Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Notional Value Derivative Asset, Notional Amount Interest Rate Investment Interest Rate Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Rollforward analysis of the activity relating to the noncontrolling interests in the operating partnership Equity, Attributable to Noncontrolling Interest [Roll Forward] Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares Add back: dilutive effect of earnings allocated to participating securities and contingently issuable shares Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted Interest Rate Swap Expiring in June 2027 Interest Rate Swap Expiring in June 2027 [Member] Interest Rate Swap Expiring in June 2027 Three Retail and Two Residential Units Three Retail and Two Residential Units [Member] Three Retail and Two Residential Units [Member] Schedule of debt and preferred equity book balance roll forward Schedule Of Debt And Preferred Equity Book Balance Roll Forward [Table Text Block] Schedule Of Debt And Preferred Equity Book Balance Roll Forward Interest Rate Swap Expiring in January 2028 Interest Rate Swap Expiring in January 2028 [Member] Interest Rate Swap Expiring in January 2028 Facility fee (as a percent) Line of Credit Facility, Commitment Fee Percentage Security Exchange Name Security Exchange Name Marketing, general and administrative Selling, General and Administrative Expense Reallocation of noncontrolling interest in the Operating Partnership Reallocation of Noncontrolling Interest In Operating Partnership, Increase (Decrease) Reallocation of Noncontrolling Interest To (From) Operating Partnership Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Other comprehensive income before reclassifications Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Stock options Employee Stock Option [Member] Financial Instruments: Derivatives and Hedging Derivative Instruments and Hedging Activities Disclosure [Text Block] Manhattan Manhattan [Member] Represents information pertaining to properties located in Manhattan. Maximum Maximum [Member] Total unrecognized compensation cost related to unvested stock awards Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Document Type Document Type Schedule of amounts due from/to related parties Schedule of Related Party Transactions [Table Text Block] Issuance of special distribution paid primarily in units Partners' Capital Account, Value, Unit Dividend Partners' Capital Account, Value, Unit Dividend Interest Rate Cap Expiring February 2024 Interest Rate Cap Expiring February 2024 [Member] Interest Rate Cap Expiring February 2024 SOFR Secured Overnight Financing Rate (SOFR) [Member] Secured Overnight Financing Rate (SOFR) Repurchases of common stock Repurchases of common units Treasury Stock, Value, Acquired, Cost Method Stock repurchase program, authorized amount Stock Repurchase Program, Authorized Amount, Total Stock Repurchase Program, Authorized Amount, Total Weighted average fair value of options granted during the period Total fair value of shares granted during the period Share Based Compensation Arrangement by Share Based Payment Award, Grants in Period Fair Value Represents the weighted average fair value of awards granted during the period. Related party receivables Increase (Decrease) in Due from Related Parties, Current Share-based Compensation Share-Based Payment Arrangement [Text Block] Other non-cash adjustments Other Noncash Income (Expense) Equity in net loss on sale of interest in unconsolidated joint venture/real estate Equity in net loss on sale of interest in unconsolidated joint venture interest/real estate (Loss) Gain on Sale Equity Method Investment, Realized Gain (Loss) on Disposal Variable rate debt Long-Term Debt, Percentage Bearing Variable Interest, Amount Derivative [Table] Derivative [Table] Customer concentration Customer Concentration Risk [Member] Lease Income Lessor, Sales-type Leases [Text Block] Real Estate Properties [Domain] Real Estate Properties [Domain] Number of company common stock issued on conversion of Series B preferred units Preferred Stock, Convertible, Conversion Ratio Variable Rate [Axis] Variable Rate [Axis] Gain (loss) on sale of real estate, net Loss on sale of real estate, net Gains (Losses) on Sales of Investment Real Estate Expenses Costs and Expenses [Abstract] Title of 12(b) Security Title of 12(b) Security Cost basis of commercial mortgage-backed securities Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, after Allowance for Credit Loss Interest Rate Swap Expiring in January 2024, 2 Interest Rate Swap Expiring in January 2024, 2 [Member] Interest Rate Swap Expiring in January 2024, 2 Interest income Interest Income, Operating Sublease Income Sublease Income Property Acquisitions Business Combination Disclosure [Text Block] Other comprehensive income attributable to noncontrolling interests Other comprehensive income attributable to noncontrolling interests Accumulated other comprehensive (loss) income allocation Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest Related Party [Domain] Related Party, Type [Domain] Interest Rate Swap Expiring February 2026, 3 Interest Rate Swap Expiring February 2026, 3 [Member] Interest Rate Swap Expiring February 2026, 3 Noncontrolling interest in the operating partnership (as a percent) Noncontrolling interest in the operating partnership (as a percent) Subsidiary, Ownership Percentage, Noncontrolling Owner Operating Segments Operating Segments [Member] Income taxes Income Tax Disclosure [Abstract] Strike Rate Derivative, Fixed Interest Rate Acquisition of subsidiary interest from noncontrolling interest Payments to Noncontrolling Interests Less: accumulated depreciation Accumulated depreciation Real Estate Investment Property, Accumulated Depreciation Mezzanine Debt Mezzanine Debt [Member] Mezzanine Debt [Member] Share-based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] Entity Tax Identification Number Entity Tax Identification Number Debt and Preferred Equity Segment Structured Finance Segment [Member] Represents the information pertaining to the reportable segment of the entity, Structured Finance Segment. Perpetual preferred stock dividends Preferred dividends Dividends, Preferred Stock Capitalized to assets associated with compensation expense related to our long-term compensation plans, restricted stock and stock options Share-Based Payment Arrangement, Amount Capitalized Statistical Measurement [Axis] Statistical Measurement [Axis] Net (loss) income attributable to SLGOP common unitholders Net (loss) income attributable to SLGOP common unitholders (numerator for diluted earnings per unit) Net Income (Loss) Allocated to, Common Unitholders This element represents amounts attributable to ROP common unitholders. Balance Sheet Location [Domain] Balance Sheet Location [Domain] Entity Interactive Data Current Entity Interactive Data Current Series L Series L Preferred Stock [Member] Series L Preferred Stock [Member] Weighted Average Leased Occupancy Real Estate, Weighted Average Leased Occupancy Real Estate, Weighted Average Leased Occupancy Adjustments to reconcile net loss to net cash provided by operating activities: Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Accounts payable, accrued expenses, other liabilities and security deposits Increase (Decrease) in Accrued Liabilities and Other The change during the period in carrying value of accounts payable, accrued expenses and fair value of hedges, due within one year or operating cycle. Summary of debt investments Schedule of Mortgage Loans on Real Estate [Table Text Block] Tabular disclosure of investments in mortgage loans on real estate. Other Assets Other Assets [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Perpetual preferred stock, annual dividends per share (in dollars per share) Preferred Stock, Dividend Rate, Per-Dollar-Amount Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Sales-type lease, lease income Sales-type Lease, Lease Income [Table Text Block] Issuance of special dividend paid primarily in stock (in shares) Stock Dividends, Shares Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Total floating rate Debt Investment with Floating Interest Rate [Member] Represents the debt investment in mortgage loans having a floating interest rate. Equity marketable securities Equity Securities, FV-NI Fungible units Share-based Compensation Arrangement By Share-based Payment Award, Number Of Fungible Units Available For Grant Share-based Compensation Arrangement By Share-based Payment Award, Number Of Fungible Units Available For Grant Counterparty Name [Axis] Counterparty Name [Axis] Net Finite Lived Intangible Liabilities, Net Represents the sum of gross carrying value of a major finite-lived intangible liability class, less accumulated amortization. Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] (Decrease) increase in unrealized value of marketable securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Purchase Price Fair Value Adjustment Gross Purchase Price Fair Value Adjustment Gross [Member] Purchase Price Fair Value Adjustment Gross Originations/Accretion SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, New Mortgage Loan Concentrations of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Transaction related costs Costs inclusive of capitalized expenses Other Cost and Expense, Operating Annual Dividend Per Unit (in dollars per share) Preferred Stock, Dividends, Per Share, Cash Paid Tenant 1 Tenant 1 [Member] Represents first tenant of the entity for which a concentration risk is disclosed. Beginning balance (in shares) Ending balance (in shares) Shares, outstanding (in shares) Units outstanding (units) Shares, Outstanding Third Amendment and Restated 2005 Stock Option and Incentive Plan Third Amendment and Restated 2005 Stock Option and Incentive Plan [Member] Third Amendment and Restated 2005 Stock Option and Incentive Plan [Member] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Class O LTIP Units Class O LTIP Units [Member] Class O LTIP Units [Member] Net cash provided by investing activities Net Cash Provided by (Used in) Investing Activities Organization Organization Ownership Interests [Line Items] -- None. No documentation exists for this element. -- Interest Rate Swaps/Caps Interest Rate Swap [Member] Debt Instrument [Axis] Debt Instrument [Axis] Credit Facility [Axis] Credit Facility [Axis] Building and improvements Investment Building and Building Improvements Series B Preferred Stock Series B Preferred Stock [Member] Schedule of combined aggregate principal maturities Schedule of Maturities of Long-Term Debt [Table Text Block] Total liabilities Liabilities Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] Mezzanine Loan, with an Initial Maturity Date of January 2025 Mezzanine Loan, with an Initial Maturity Date of January 2025 [Member] Mezzanine Loan, with an Initial Maturity Date of January 2025 [Member] Stabilization of property, three years or more after stabilization, percent Related Party Transaction, Stabilization Of Property, Three Years Or More After Stabilization, Percent Related Party Transaction, Stabilization Of Property, Three Years Or More After Stabilization, Percent Interest rate, fixed rate debt (as a percent) Long-Term Debt, Percentage Bearing Fixed Interest, Percentage Rate Rental revenue decrease from amortization of acquired leases Rental Revenue Increase (Decrease) Acquired Lease Amortization Represents the increase (decrease) in rental revenue during the period resulting from the net amortization of acquired above-market and below-market leases. Contribution to consolidated joint venture interests Consolidation of Joint Venture Interest This element represent the net income (loss) in consolidation of joint venture interest. Schedule of common stock issued and proceeds received dividend reinvestments Schedule of Common Stock Issued and Proceeds Received Dividend Reinvestments [Table Text Block] Schedule of Common Stock Issued and Proceeds Received Dividend Reinvestments [Table Text Block] Related Party Transaction [Domain] Related Party Transaction [Domain] Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] Investment in Marketable Securities Marketable Securities, Policy [Policy Text Block] Fair value of security in a continuous unrealized loss position for less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Noncontrolling interests in the Operating Partnership Net loss Noncontrolling Interest in Net Income (Loss) Operating Partnerships, Redeemable 2 - Watch List Assets - Higher potential for loss Risk Level, Medium [Member] Employee Stock Purchase Plan Employee Stock Purchase Plan [Member] Employee Stock Purchase Plan [Member] Share of joint venture of accumulated other comprehensive loss reclassified into equity in net income from unconsolidated joint ventures within the next 12 months Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months into Equity in Net Income Represents the estimated net amount of existing gains (losses) on cash flow hedges at the reporting date expected to be reclassified to equity in net income within the next 12 months. Interest Rate Cap Expiring November 2023, 2 Interest Rate Cap Expiring November 2023, 2 [Member] Interest Rate Cap Expiring November 2023, 2 Series I Preferred Stock Series I Preferred Units Preferred Stock [Member] Schedules of concentration of risk, by risk factor Schedules of Concentration of Risk, by Risk Factor [Table Text Block] Prudential Real Estate Investors Prudential Real Estate Investors [Member] Prudential Real Estate Investors Interest Rate Swap Expiring in February 2027, 2 Interest Rate Swap Expiring in February 2027, 2 [Member] Interest Rate Swap Expiring in February 2027, 2 Holiday Holiday [Member] Holiday Other liabilities Other Liabilities One Vanderbilt Avenue One Vanderbilt Avenue [Member] One Vanderbilt Avenue Share repurchased (in shares) Stock Repurchased During Period, Shares 11 West 34th Street 11 West 34th Street West 11 Street 34 [Member] Represents the information pertaining to 11 West 34th Street, a joint venture property of the entity. Third-Party Third-Party [Member] Third-Party Schedule of Ownership Interests [Table] Schedule of Ownership Interests [Table] Represents information related to ownership interests held by the entity. Percentage of concentration (percent) Concentration Risk, Percentage Contributions of net proceeds from sale of preferred stock Proceeds from Issuance of Preferred Stock and Preference Stock Stockholders Equity [Table] Stockholders Equity [Table] Disclosure of information pertaining to changes in stockholders' equity during the period. Schedule of accumulated other comprehensive loss Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Authorized shares, par value (in dollars per share) Total Par or Stated Value Per Share Face amount or stated value of capital stock per share; generally not indicative of the fair market value per share. Debt and preferred equity investments, discount and deferred origination fees Discount of Structured Finance Investments This item represents the net amount of discounts related to investments in structured finance investments. Mezzanine Loan Due May 2024 Mezzanine Loan Due May 2024 [Member] Mezzanine Loan Due May 2024 Korean Institutional Investor / Israeli Institutional Investor Korean Institutional Investor / Israeli Institutional Investor [Member] Korean Institutional Investor / Israeli Institutional Investor Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Class of Stock [Axis] Class of Stock [Axis] Investments in Unconsolidated Joint Ventures Equity Method Investments and Joint Ventures Disclosure [Text Block] Unsecured notes, net Unsecured Debt Depreciation and amortization Depreciation, Depletion and Amortization Deferred costs, net Deferred costs, net Deferred Costs Business Combination and Asset Acquisition [Abstract] Mezzanine Loan Due January 2026 Mezzanine Loan Due January 2026 [Member] Mezzanine Loan Due January 2026 Consolidation Items [Axis] Consolidation Items [Axis] Estimated fair value of debt and preferred equity investments, low end of range Mortgage Loans on Real Estate, Fair Value, Low End of Range Represents the low end of the range of estimated fair value for investments in mortgage loans on real estate. Number of increases to share repurchase program Share Repurchase Program, Number Of Increases To Share Repurchase Program Share Repurchase Program, Number Of Increases To Share Repurchase Program Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] 485 Lexington Avenue Lexington Avenue, 485 [Member] Represents the information pertaining to 485 Lexington Avenue, a property owned by the entity. Total fixed rate Fixed Rate [Member] Fixed Rate [Member] Restricted cash Restricted Cash and Cash Equivalents Operating lease rent Operating Lease, Annual Expense Operating Lease, Annual Expense Redemption of OP units Payments for Repurchase of Other Equity Net unrealized gain (loss) on derivative instruments Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Series I Preferred Stock Series I Preferred Units Series I Preferred Stock [Member] Outstanding nonredeemable series I preferred stock or outstanding series I preferred stock. Classified within stockholders' equity if nonredeemable or redeemable solely at the option of the issuer. Classified within temporary equity if redemption is outside the control of the issuer. Stock options, stock appreciation rights and other awards Stock Options Stock Appreciation Rights and Other Awards [Member] Represents the stock options, stock appreciation rights and other awards granted by the entity. Thes do not deliver full value and have an expiration date. Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Entity Emerging Growth Company Entity Emerging Growth Company National Pension Service of Korea / Hines Interest LP National Pension Service of Korea / Hines Interest LP [Member] National Pension Service of Korea / Hines Interest LP Service Corporation Service Corporation [Member] Service Corporation [Member] Deferred financing costs, net Debt Issuance Costs, Net Excess stock, shares authorized (shares) Excess Stock, Shares Authorized Operating lease, lease income Operating Lease, Lease Income [Table Text Block] Preferred equity investment originations/accretion Preferred equity investments Preferred Equity Investments in Mortgage Loans [Member] Represents preferred equity investments in mortgage loans on real estate. Diluted weighted average common units and common unit equivalents outstanding (in shares) Diluted weighted average common units outstanding (shares) Weighted Average Limited Partnership Units Outstanding, Diluted Number of stores Number of Stores Common Stock Common Stock [Member] Options granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures Exchange of preferred equity investment for real estate or equity in joint venture Exchange Of Preferred Equity Investment For Real Estate Or Equity In Joint Venture Exchange Of Preferred Equity Investment For Real Estate Or Equity In Joint Venture National Pension Service of Korea / Hines Interest LP / International Investor National Pension Service of Korea / Hines Interest LP / International Investor [Member] National Pension Service of Korea / Hines Interest LP / International Investor Entity Address, Postal Zip Code Entity Address, Postal Zip Code Income Statement Location [Domain] Income Statement Location [Domain] Managed office properties Managed Office Properties [Member] Represents the office properties managed by the entity. Repayments of mortgages and other loans payable Repayments of Secured Debt Fair value measurements, recurring and nonrecurring Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Contribution to consolidated joint venture interest Contribution To Consolidated Joint Venture Interest Contribution To Consolidated Joint Venture Interest Total mortgages and other loans payable Secured Debt, Gross Secured Debt, Gross SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] SEC Schedule, 12-29, Real Estate Companies, Investment in Movement in Mortgage Loans on Real Estate [Roll Forward] Weighted Average Yield at End of Period Debt, Weighted Average Interest Rate Total equity Beginning balance Ending balance Equity Equity, Including Portion Attributable to Noncontrolling Interest Cash distributions to noncontrolling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Diluted (loss) earnings per unit (in dollars per share) Net Income (Loss), Net of Tax, Per Outstanding Limited Partnership Unit, Diluted Minimum Minimum [Member] Denominator Weighted Average Number of Shares Outstanding, Diluted [Abstract] Distributions of cumulative earnings from unconsolidated joint ventures Proceeds from Equity Method Investment, Distribution Unaudited Approximate Usable Square Feet Approximate Square Feet unaudited (sqft) Unaudited Approximate Square Feet (sqft) Area of Real Estate Property Estimated fair value of debt and preferred equity investments, high end of range Mortgage Loans on Real Estate Fair Value, High End of Range Represents the high end of the range of estimated fair value for investments in mortgage loans on real estate. Other investments Payments For (Proceeds From) Other Investments Payments For (Proceeds) Other Investments Payment Of Interest Acquired Payment Of Interest Acquired [Member] Payment Of Interest Acquired Other comprehensive income Other Comprehensive Income (Loss), Net of Tax Estimated current balance held in accumulated other comprehensive loss to be reclassified into earnings within the next 12 months Cash Flow Hedge Gain (Loss) to be Reclassified within 12 Months Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Assets Assets [Abstract] Lease liability - operating leases Increase (Decrease) in Operating Lease Liability Tax withholdings related to restricted share awards Payment, Tax Withholding, Share-Based Payment Arrangement Liabilities Liabilities [Abstract] 1515 Broadway Broadway, 1515 [Member] Represents the information pertaining to 1515 Broadway, a property owned by the entity. Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Retained Earnings Retained Earnings [Member] Interest expense Interest Income (Expense), Net [Abstract] Interest Rate Swap Expiring in February 2027, 4 Interest Rate Swap Expiring in February 2027, 4 [Member] Interest Rate Swap Expiring in February 2027, 4 Increase in unrealized value of derivative instruments, including SL Green's share of joint venture derivative instruments Increase in unrealized value of derivative instruments, including SLGOP's share of joint venture derivative instruments Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Basic (loss) earnings per share (in dollars per share) Earnings Per Share, Basic 1552-1560 Broadway Broadway 1552 to 1560 [Member] Represents the information pertaining to 1552-1560 Broadway, a joint venture property of the entity. Accounting Policies [Abstract] Accounting Policies [Abstract] Number of tenants (tenants) Number of Tenants Represents the number of tenants to whom the facility is leased. Class of Treasury Stock [Table] Class of Treasury Stock [Table] Annualized rent Annualized Rent [Member] Annualized rent, when it serves as a benchmark in a concentration of risk calculation. Principles of Consolidation Consolidation, Policy [Policy Text Block] In-place leases In Place Leases [Member] Represents information pertaining to in-place leases. Remaining 2023 Future Amortization of Debt, Remainder Of Fiscal Year Future Amortization of Debt, Remainder Of Fiscal Year Proceeds from issuance of debt Proceeds from Issuance of Debt Document Transition Report Document Transition Report Interest Expense Interest Expense [Member] Total commercial real estate properties, net Commercial real estate property, net Real Estate Investment Property, Net Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward] Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward] Accumulated Other Comprehensive Income (Loss) of the Company [Roll Forward] DRSPP proceeds Stock Issued During Period, Value, Dividend Reinvestment Plan Identified intangible liabilities (included in deferred revenue): Finite Lived Intangible Liabilities [Abstract] -- None. No documentation exists for this element. -- Investment in Marketable Securities Fair Value of Financial Instruments Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Net equity investment in VIEs in which the entity is not primary beneficiary Variable Interest Entity Not Primary Beneficiary, Investment Represents the amount of equity investment in variable interest entities (VIEs) in which the entity is not a primary beneficiary. Derivative Instrument [Axis] Derivative Instrument [Axis] Ownership percentage deconsolidated Equity Method Investment, Ownership Percentage, Deconsolidated Equity Method Investment, Ownership Percentage, Deconsolidated Unpaid Principal Balance Long-Term Debt, Gross Dividend Reinvestment and Stock Purchase Plan (DRIP) Dividend Reinvestment and Stock Purchase Plan [Member] Represents the dividend reinvestment and stock purchase plan of the entity. Properties Sold Properties Sold [Member] Properties Sold Security deposits Security Deposit Liability Trust Preferred Securities Junior Subordinated Debt [Member] Senior Financing Mortgage Loans on Real Estate, Senior Financing Mortgage Loans on Real Estate, Senior Financing Noncontrolling interests in Operating Partnership Redeemable Noncontrolling Interest, Equity, Common, Carrying Amount Deferred Stock Compensation Plan for Directors Deferred Stock Compensation Plan for Directors [Member] Represents the Deferred Stock Compensation Plan for Directors of the entity. Limited partner interests in SLGOP (4,139 and 3,670 limited partner common units outstanding at September 30, 2023 and December 31, 2022, respectively) Limited Partners' Capital Account Israeli Institutional Investor Israeli Institutional Investor [Member] Israeli Institutional Investor Canadian Pension Plan Investment Board Canadian Pension Plan Investment Board [Member] Canadian Pension Plan Investment Board Deferred compensation plan and stock awards, net of forfeitures and tax withholdings Deferred Compensation Plan and Stock Award, Net Value of stock issued during the period from a deferred compensation plan and stock award, net. Debt and Preferred Equity Investments Debt And Preferred Equity Investments [Policy Text Block] Debt And Preferred Equity Investments [Policy Text Block] Proceeds from stock options exercised and DRSPP issuance Proceeds from Stock Options Exercised Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Private Investors Private Investors [Member] Private Investors Residential Residential Real Estate [Member] Interest Rate Cap Expiring June 2024 Interest Rate Cap Expiring June 2024 [Member] Interest Rate Cap Expiring June 2024 Repayments or redemption of debt and preferred equity investments Repayments Or Redemption Of Debt And Preferred Equity Investments Repayments Or Redemption Of Debt And Preferred Equity Investments Lease liability - financing leases Finance Lease, Liability Deferred lease costs Increase (Decrease) in Deferred Leasing Fees Canceled (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Fungible units per share (in fungible units per share) Share Based Compensation Arrangement by Share Based Payment Award, Fungible Units For Each Share Share Based Compensation Arrangement by Share Based Payment Award, Fungible Units For Each Share SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Loan Type [Axis] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Loan Type [Axis] Investments in Unconsolidated Joint Ventures Equity Method Investments [Policy Text Block] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Loan Type [Domain] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Loan Type [Domain] Allianz Real Estate of America Allianz Real Estate of America [Member] Allianz Real Estate of America Schedule of commercial office properties Schedule of Real Estate Properties [Table Text Block] Interest Rate Swap Expiring in May 2027, 2 Interest Rate Swap Expiring in May 2027, 2 [Member] Interest Rate Swap Expiring in May 2027, 2 Stabilization period Related Party Transaction, Stabilization Period Related Party Transaction, Stabilization Period Distributions in excess of cumulative earnings from unconsolidated joint ventures Proceeds from Equity Method Investment, Distribution, Return of Capital Net change in loan loss reserves SEC Schedule, 12-29, Real Estate Companies, Investment In Mortgage Loans On Real Estate, Loan Loss Reserve Period Increase (Decrease) SEC Schedule, 12-29, Real Estate Companies, Investment In Mortgage Loans On Real Estate, Loan Loss Reserve Period Increase (Decrease) Deferred revenue Deferred Revenue 2024 Long-Term Debt, Maturity, Year One Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Other assets Other Assets Wells Fargo Wells Fargo [Member] Wells Fargo Write down of value in leasehold interest SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Write-down or Reserve, Amount Stock-based compensation plans (shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Total joint venture mortgages and other loans payable, net Secured Debt and Other Loans, Payable, Net Secured Debt and Other Loans, Payable, Net 2025 Future Amortization of Debt, Third Full Fiscal Year The amount of amortization of debt expected to be recognized during the third full fiscal year following the date of the most recent balance sheet. Interest Rate Cap Expiring September 2024 Interest Rate Cap Expiring September 2024 [Member] Interest Rate Cap Expiring September 2024 Scheduled Amortization Future Amortization of Debt [Abstract] -- None. No documentation exists for this element. -- Document Period End Date Document Period End Date Preferred Equity Preferred Equity [Member] Preferred Equity [Member] Treasury Stock Treasury Stock, Common [Member] Period of restriction to redeem OP Units Common Units Redemption, Period Of Restriction Common Units Redemption, Period Of Restriction Segment information Segment Reporting Information [Line Items] Tenant and other receivables Tenant and other receivables, related party receivables, and deferred rents receivable Accounts and Financing Receivable, after Allowance for Credit Loss Diluted Earnings: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Effect of Dilutive Securities: Dilutive Securities, Effect on Basic Earnings Per Share [Abstract] Federal, state and local tax provision Income Tax Expense (Benefit) Limited partner interests in Operating Partnership, limited partner common units outstanding (shares) Limited Partners' Capital Account, Units Outstanding Interest Rate Cap Expiring November 2023 Interest Rate Cap Expiring November 2023 [Member] Interest Rate Cap Expiring November 2023 Fair Value Measurements Fair Value Disclosures [Text Block] Distributions to noncontrolling interests in the Operating Partnership Distribution to Noncontrolling Interest Operating Partnership The cash outflow for distributions to partners in a partnership. Amounts reclassified from accumulated other comprehensive income Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Balance at beginning of period Balance at end of period Noncontrolling Interest in Preferred Unit Holders Redemption of preferred stock Redemption of preferred units Payments for Repurchase of Redeemable Preferred Stock Restricted Stock Awards Restricted Stock Awards [Member] Represents the restricted stock awards granted by the entity. Restricted stock are shares of stock for which sale is contractually or governmentally restricted for a given period of time. Operating expenses, including related party expenses of $2 and $3 in 2023, and $0 and $5,695 in 2022 Operating expenses Operating Costs and Expenses Equity [Abstract] Equity [Abstract] Below-market leases Leases, Below Market [Member] Leases, Below Market [Member] Investment fair value adjustment Assets, Fair Value Adjustment Contributions from noncontrolling interests in other partnerships Proceeds from Noncontrolling Interests in Other Partnerships The cash inflow from the capital received in cash from a partner in a consolidated partnership during the period. Cash and cash equivalents Cash and restricted cash Cash and Cash Equivalents, at Carrying Value Comprehensive (loss) income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Financing Receivable, Credit Quality Indicator [Table] Financing Receivable, Credit Quality Indicator [Table] Schedule of first mortgage notes payable collateralized by the respective joint venture properties and assignment of leases Schedule of Mortgage and Other Loans Payable on Joint Venture Properties [Table Text Block] Tabular disclosure of the information pertaining to mortgage and other loans payable on joint venture properties of the entity. Capital Partners' Capital, Including Portion Attributable to Noncontrolling Interest [Abstract] Interest Rate Cap Expiring June 2023 Interest Rate Cap Expiring June 2023 [Member] Interest Rate Cap Expiring June 2023 Landmark Square Landmark Square [Member] Represents the information pertaining to Landmark Square, a property owned by the entity. Credit Facility [Domain] Credit Facility [Domain] Repurchases of common stock (in shares) Repurchases of common units (in units) Treasury Stock, Shares, Acquired Debt disclosures by scheduled maturity date Debt Instrument, Information by Scheduled Maturity Date of Debt [Abstract] -- None. No documentation exists for this element. -- Interest rate added to base rate (as a percent) Debt Instrument, Basis Spread on Variable Rate New York State Teacher's Retirement System New York State Teacher's Retirement System [Member] New York State Teacher's Retirement System Estimated useful life (in years) Property, Plant and Equipment, Useful Life Basic Earnings: Net Income (Loss) Available to Common Stockholders, Basic [Abstract] Debt Investments Held [Abstract] Debt Investments Held [Abstract] Debt Investments Held [Abstract] Acquisitions of real estate property Payments to Acquire Commercial Real Estate Proceeds from revolving credit facility, term loans and unsecured notes Proceeds from Issuance of Unsecured Debt Future Funding Obligations Loans and Leases Receivable, Funding Obligation Loans and Leases Receivable, Funding Obligation Interest Rate Contract Interest Rate Contract [Member] 2021 Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year Net income (loss) Profit (Loss) Less Minority Interest in Net Income (Loss) Operating Partnerships Net income including minority interest in partnerships. 717 Fifth Avenue Fifth Avenue, 717 [Member] Represents the information pertaining to 717 Fifth Avenue, a joint venture property of the entity. Additional Paid- In-Capital Additional Paid-in Capital [Member] Senior Financing Mortgage Loans on Real Estate, Senior Debt on Investment Amount as of the balance sheet date of debt which holds a position senior to the entity's investment in a mortgage loan on real estate. Effect of Dilutive Securities: Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract] Interest Rate Swap Expiring January 2024 Interest Rate Swap Expiring January 2024 [Member] Interest Rate Swap Expiring January 2024 [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Repayments of revolving credit facility, term loans and unsecured notes Repayments of Unsecured Debt Debt instrument, face amount, higher borrowing capacity option Debt Instrument, Face Amount, Higher Borrowing Capacity Option Debt Instrument, Face Amount, Higher Borrowing Capacity Option Equity in net loss from unconsolidated joint ventures Equity in net loss from unconsolidated joint ventures Company's equity in net loss from unconsolidated joint ventures Income (Loss) from Equity Method Investments Shares issued (in shares) Deferred Compensation Arrangement with Individual, Shares Issued Cover [Abstract] Cover [Abstract] Deferred revenue Increase (Decrease) in Deferred Liabilities Amortization of deferred financing costs Amortization of Debt Issuance Costs Interest capitalized Capitalized Interest Costs, Including Allowance for Funds Used During Construction Basic weighted average common units outstanding (in shares) Weighted Average Limited Partnership Units Outstanding, Basic Number of shares to be received on redemption of one unit of limited partnership interests (shares) Number of Shares on Redemption of One Unit of Partnership Interest Represents the number of shares of the common stock of the entity, which the limited partner of the operating partnership is entitled to receive on redemption of one unit of interest in the partnership. Deconsolidation of a subsidiary Deconsolidation Real Estate Investments Represents the change in the carrying value of real estate investments resulting from deconsolidation. Dividends paid on common and preferred stock Distributions paid on common and preferred units Payments of Dividends Lapsed or canceled (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period Equity Stockholders Equity Including Portion Attributable to Noncontrolling Interest in Other Partnership [Abstract] -- None. No documentation exists for this element. -- Segment Information Segment Reporting Disclosure [Text Block] Net (decrease) increase in cash, cash equivalents, and restricted cash Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Maximum percentage of the annual retainer fee, chairman fees and meeting fees that may be deferred by non-employee directors (percent) Deferred Compensation Arrangement with Individual Maximum Percentage of the Compensation that May be Deferred Represents the maximum percentage of the compensation that may be deferred by employees of the entity under deferred compensation plans. Deferred financing costs, net of amortization Secured Debt, Deferred Finance Costs, Net Secured Debt, Deferred Finance Costs, Net Equity Component [Domain] Equity Component [Domain] Entity Current Reporting Status Entity Current Reporting Status Concentration Risk Type [Domain] Concentration Risk Type [Domain] Marketable securities, unrealized loss Marketable Security, Unrealized Gain (Loss) Equity method investments with negative book value Equity Method Investments With Negative Book Value Equity Method Investments With Negative Book Value Beginning balance (units) Ending balance (units) Partners' Capital Account, Units Interest Rate Swap Expiring January 2026 Interest Rate Swap Expiring January 2026 [Member] Interest Rate Swap Expiring January 2026 [Member] Accrued interest payable Accrued Interest Payable and Other Represents accrued interest and fair value of hedges entered into by the Entity. Consolidated Entities [Domain] Consolidated Entities [Domain] Loan loss and other investment reserves, net of recoveries Loan loss reserves and other investment reserves, net of recoveries Current period provision for loan loss Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal) SUMMIT One Vanderbilt SUMMIT One Vanderbilt [Member] SUMMIT One Vanderbilt Economic Interest Equity Method Investment, Economic Interest Percentage The percentage of economic interest in the investee accounted for under the equity method of accounting. Business Segments [Axis] Segments [Axis] Fair Value Estimate of Fair Value Measurement [Member] Other comprehensive income: Other Comprehensive Income (Loss), Net of Tax [Abstract] Revolving credit facility, net Long-Term Line of Credit Real estate properties Real Estate Properties [Line Items] Development/Redevelopment Development Properties [Member] Represents the development properties owned by the entity. Real Estate, Type of Property [Axis] Real Estate, Type of Property [Axis] A Fund Managed By Meritz Alternative Investment Management A Fund Managed By Meritz Alternative Investment Management [Member] A Fund Managed By Meritz Alternative Investment Management Consolidated Entities [Axis] Consolidated Entities [Axis] Variable Rate [Domain] Variable Rate [Domain] Net loss (income) attributable to noncontrolling interests and preferred units distributions Net Income (Loss) Attributable to Noncontrolling Interest Statistical Measurement [Domain] Statistical Measurement [Domain] Wharton Properties Wharton Properties [Member] Wharton Properties Partner Capital Components [Domain] Partner Capital Components [Domain] Preferred stock, liquidation preference (in dollars per share) Perpetual preferred stock, liquidation preference (in dollars per share) Preferred Stock, Liquidation Preference Per Share Retail Retail Properties [Member] Represents information pertaining to retail properties owned by the entity. Changes in fair value Accumulated Other Comprehensive Income Loss Gain Loss from Changes in Fair Value Accumulated Other Comprehensive Income Loss Gain Loss from Changes in Fair Value Awards outstanding (in shares) Balance at beginning of year (in shares) Balance at end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Building leasehold and improvements Building Leasehold Improvements, Gross Carrying amount at the balance sheet date of long-lived, depreciable asset that is an addition or improvement to assets held under lease arrangement as well as the initial investment in a leasehold interest. Mortgages and Other Loans Payable Corporate Indebtedness Debt Disclosure [Text Block] Cash distributions declared Partners' Capital Account, Distributions Authorized capital stock (shares) Total Shares Authorized The maximum number of total capital shares permitted to be issued by an entity's charter and bylaws. Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Interest Rate Swap Expiring January 2026, 2 Interest Rate Swap Expiring January 2026, 2 [Member] Interest Rate Swap Expiring January 2026, 2 [Member] Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Revolving Credit Facility Revolving Credit Facility [Member] Service Corporation Variable Interest Entity, Primary Beneficiary [Member] Schedule of investment in financing receivables and risk rating Schedule Of Investment In Financing Receivables And Risk Rating [Table Text Block] Schedule Of Investment In Financing Receivables And Risk Rating 650 Fifth Avenue Fifth Avenue, 650 [Member] 650 Fifth Avenue [Member] Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments and Joint Ventures [Abstract] Performance Shares Performance Shares [Member] Real Estate by Location [Domain] Real Estate by Location [Domain] Identifies real estate properties of the entity by location. Segment Reporting [Abstract] Segment Reporting [Abstract] Remaining average contractual life of the options exercisable (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Discontinued Operations and Disposal Groups [Abstract] Discontinued Operations and Disposal Groups [Abstract] Investment, Name [Axis] Investment, Name [Axis] 719 Seventh Avenue Seven One Nine Seventh Avenue [Member] Seven One Nine Seventh Avenue [Member] Commitments and contingencies Commitments and Contingencies Dividend reinvestments/stock purchases under the DRSPP Proceeds from Issuance of Common Stock Partners' Interest General Partner [Member] Total commercial real estate properties, at cost Real Estate Investment Property, at Cost Winthrop Capital Advisors Winthrop Capital Advisors [Member] Winthrop Capital Advisors Schedule of components of deferred costs Schedule of Deferred Costs [Table Text Block] Tabular disclosure of the components of deferred costs. Concentration of Credit Risk Concentration Risk [Line Items] Contingently issuable units (in shares) Incremental Common Units Attributable to Dilutive Effect of Nonvested Shares with Forfeitable Dividends Incremental Common Units Attributable to Dilutive Effect of Nonvested Shares with Forfeitable Dividends Deferred Lease Costs and Lease Classification Lessee, Leases [Policy Text Block] Total fixed rate and floating rate debt Secured Debt and Other Loans, Payable Represents the carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations and other loans payable. Revenue Recognition Revenue [Policy Text Block] Noncontrolling Interest [Abstract] Noncontrolling Interest [Abstract] Financing Receivable, Nonaccrual [Line Items] Financing Receivable, Nonaccrual [Line Items] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Restricted Cash Restricted Cash [Policy Text Block] Restricted Cash 2012 Credit Facility Revolving Credit Facility Credit Facility 2012 [Member] Represents information pertaining to 2012 Credit Facility. Additional amount of financing receivables included in other assets Total after allowance for loan loss Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss Interest rate cap and swap agreements (included in Other liabilities) Derivative Liability, Subject to Master Netting Arrangement, before Offset Mortgages and other loans payable, net Total mortgages and other loans payable, net Secured Debt Number of securities repaid Debt Securities, Available-For-Sale, Number Of Securities Repaid Debt Securities, Available-For-Sale, Number Of Securities Repaid Land and land interests Land Total fixed rate debt Secured Debt, Bearing Fixed Interest, Amount The portion of the carrying amount of long-term secured loans outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate. Level 3 Fair Value, Inputs, Level 3 [Member] Treasury stock, shares (in shares) Treasury Stock, Common, Shares Unrealized loss Debt Securities, Available-for-Sale, Unrealized Loss Lease Income Lessor, Operating Leases [Text Block] Balance at beginning of period (in shares) Balance at end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number Three Mortgage Investments Three Mortgage Investments [Member] Three Mortgage Investments 625 Madison Avenue Madison Avenue, 625 [Member] Represents the information pertaining to 625 Madison Avenue, a property owned by the entity. Commercial mortgage-backed securities Marketable securities available-for-sale Debt Securities, Available-for-Sale, Excluding Accrued Interest Debt and preferred equity investments including investments held by unconsolidated joint ventures Mortgage Loans on Real Estate, Commercial and Consumer, Net Including Debt Investments, Other Mortgage Loans on Real Estate, Commercial and Consumer, Net Including Debt Investments, Other Allowance for credit losses on financing receivables Financing Receivable, Allowance for Credit Loss [Table Text Block] Investment income Investment Income, Interest and Dividend Total Long-Term Debt, Fair Value Origination of debt and preferred equity investments Origination Of Debt And Preferred Equity Investments Origination Of Debt And Preferred Equity Investments Net (loss) income attributable to SL Green Net Income (Loss) Derivative Contract [Domain] Derivative Contract [Domain] Financing Receivables, Equal to Greater than 90 Days Past Due Financial Asset, Equal to or Greater than 90 Days Past Due [Member] Private Investor / Wharton Properties Private Investor / Wharton Properties [Member] Private Investor / Wharton Properties Shares, issued (in shares) Shares, Issued Liabilities and equity Liabilities and Equity [Abstract] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Exercised (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Amount of Gain Recognized in Other Comprehensive (Loss) Income Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Interest Rate Swap Expiring February 2026 Interest Rate Swap Expiring February 2026 [Member] Interest Rate Swap Expiring February 2026 Exchange of debt investment for real estate or equity in joint venture Transfer from Investments Mortgages and Other Loans Payable Mortgages and Other Loans Payable -- None. No documentation exists for this element. -- Options vesting period (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Measurement Basis [Axis] Measurement Basis [Axis] Discount from market price Share-Based Compensation Arrangement by Share-Based Payment Award, Discount from Market Price, Offering Date Aggregate termination value Assets Needed for Immediate Settlement, Aggregate Fair Value 280 Park Avenue 280 Park Avenue Park Avenue, 280 [Member] Represents the information pertaining to 280 Park Avenue, a joint venture property of the entity. Tenant and other receivables Increase (Decrease) in Accounts Receivable Fair Value Measurement [Domain] Fair Value Measurement [Domain] SL Green Operating Partnership Subsidiaries [Member] Remaining 2023 Long-Term Debt, Maturity, Remainder of Fiscal Year Cash distributions declared (per common unit, none of which represented a return of capital for federal income tax purposes) (in dollars per share) Common Stock, Dividends, Per Share, Declared Net proceeds from disposition of real estate/joint venture interest Proceeds from Real Estate and Real Estate Joint Ventures Real Estate Property Ownership [Axis] Real Estate Property Ownership [Axis] Summary of preferred equity investments Investments Classified by Contractual Maturity Date [Table Text Block] Recorded investment, nonaccrual status Financing Receivable, Nonaccrual Term Initial Term (in Years) Debt Instrument, Term Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Real Estate Segment Real Estate Segment [Member] Represents the information pertaining to the reportable segment of the entity, Real Estate Segment. Ownership interest sold Disposal Group, Including Discontinued Operation, Ownership Interest Disposed Disposal Group, Including Discontinued Operation, Ownership Interest Disposed Income Statement Location [Axis] Income Statement Location [Axis] Shares of common stock issued (shares) Common Stock, Shares Held in Employee Trust, Shares Excess shares issued (shares) Excess Stock, Shares Issued Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Acquisition deposits and deferred purchase price Payments For (Proceeds From) Acquisition Deposits And Deferred Purchase Price Payments For (Proceeds From) Acquisition Deposits And Deferred Purchase Price Schedule of Real Estate Properties [Table] Schedule of Real Estate Properties [Table] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Fair value, by balance sheet grouping Fair Value, by Balance Sheet Grouping [Table Text Block] Dividends paid on preferred units Noncontrolling Interest, Decrease From Distribution On Preferred Units Noncontrolling Interest, Decrease From Distribution On Preferred Units Product and Service [Domain] Product and Service [Domain] Commercial mortgage-backed securities Commercial Mortgage-Backed Securities [Member] Deferred loan costs Proceeds from (Payments of) Financing Costs Proceeds from (Payments of) Financing Costs Office Office Properties [Member] Represents the investment in office properties owned by the entity. Noncontrolling interests in other partnerships Nonredeemable Noncontrolling Interest Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Plan Name [Domain] Plan Name [Domain] Number of extensions Line Of Credit Facility, Number Of Extensions Line Of Credit Facility, Number Of Extensions Interest expense before capitalized interest Interest Expense Tenant improvements and capital expenditures payable Capital Expenditures Incurred but Not yet Paid Loss on early extinguishment of debt Gain (Loss) on Extinguishment of Debt Remaining weighted average contractual life of the options outstanding (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Total lease payments Operating Lease Lease Income Fixed And Variable Lease Payments Operating Lease Lease Income Fixed And Variable Lease Payments Schedule of consolidated interest expense, excluding capitalized interest Interest Income and Interest Expense Disclosure [Table Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Preferred units distributions Noncontrolling Interest in Net Income (Loss) Preferred Unit Holders, Redeemable Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Entity File Number Entity File Number 2026 Long-Term Debt, Maturity, Year Three Financing Receivable, Nonaccrual [Table] Financing Receivable, Nonaccrual [Table] Net unrealized loss on marketable securities AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] Number of Units Authorized (in shares) Preferred Units, Authorized Interest Rate Swap Expiring February 2026, 2 Interest Rate Swap Expiring February 2026, 2 [Member] Interest Rate Swap Expiring February 2026, 2 Entity Shell Company Entity Shell Company One Madison Avenue One Madison Avenue [Member] One Madison Avenue Add back: effect of dilutive securities (redemption of units to common shares) Dilutive Securities, Effect on Basic Earnings Per Share, Dilutive Convertible Securities Cash, cash equivalents, and restricted cash at beginning of year Cash, cash equivalents, and restricted cash at end of period Total cash, cash equivalents, and restricted cash Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents Investment in joint venture, partners' ownership percentage Investment in Joint Venture, Partners' Ownership Percentage Investment in Joint Venture, Partners' Ownership Percentage Accounts payable and accrued expenses Accounts Payable and Accrued Liabilities Interest Rate Cap Expiring August 2024 Interest Rate Cap Expiring August 2024 [Member] Interest Rate Cap Expiring August 2024 Operating lease rent Operating Lease, Cost Common stock, shares issued (in shares) Common Stock, Shares, Issued Vested during the period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Interest Rate Swap Expiring in January 2024, 3 Interest Rate Swap Expiring in January 2024, 3 [Member] Interest Rate Swap Expiring in January 2024, 3 Percentage of ownership in SL Green Management LLC owned by operating partnership (percent) Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest Treasury stock at cost Treasury Stock, Common, Value Long-term debt, carrying value Long-Term Debt 2027 Long-Term Debt, Maturity, Year Four Excess shares outstanding (in shares) Excess Stock, Shares Outstanding Weighted average period for recognition of compensation cost related to unvested stock awards (in years) Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Noncontrolling Interests on the Company's Consolidated Financial Statements Noncontrolling Interest Disclosure [Text Block] Comprehensive (loss) income attributable to SL Green Comprehensive Income (Loss), Net of Tax, Attributable to Parent Revolving Credit Facility, Maturity May 2026 Revolving Credit Facility, Maturity May 2026 [Member] Revolving Credit Facility, Maturity May 2026 [Member] Series F Series F Preferred Stock [Member] SL Green Management SLGreenManagement [Member] SLGreenManagement [Member] Interest rate, floating rate debt (as a percent) Long-Term Debt, Percentage Bearing Variable Interest, Percentage Rate Entity Address, Address Line One Entity Address, Address Line One Schedule of combined balance sheets for the unconsolidated joint ventures Equity Method Investments, Summarized Financial Information Balance Sheet [Table Text Block] Disclosure of summarized balance sheet financial information for investments accounted for using the equity method of accounting. Total floating rate debt Secured Debt, Bearing Variable Interest, Amount The portion of the carrying amount of long-term secured loans outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time. Mezzanine Loan Due June 2023, 2 Mezzanine Loan Due June 2023, 2 [Member] Mezzanine Loan Due June 2023, 2 7 Dey / 185 Broadway 7 Dey/185 Broadway [Member] 7 Dey/185 Broadway Combined statements of income for the unconsolidated joint ventures Income Statement [Abstract] Shares of common stock issued (in shares) Stock Issued During Period, Shares, New Issues Senior unsecured notes Senior Unsecured Notes [Member] Senior Unsecured Notes [Member] Financing Receivable, Credit Quality Indicator [Line Items] Financing Receivable, Credit Quality Indicator [Line Items] Numerator Net Income (Loss) Attributable to Parent [Abstract] Class of Stock [Line Items] Class of Stock [Line Items] Interest payment deferment, number of consecutive quarters Debt Instrument, Interest Payment Deferment, Number Of Consecutive Quarters Debt Instrument, Interest Payment Deferment, Number Of Consecutive Quarters Number of marketable securities sold Debt Securities, Available For Sale, Number Of Securities Sold Debt Securities, Available For Sale, Number Of Securities Sold Less: distributed earnings allocated to participating securities Distributed Earnings Investment Property Concentration Risk Investment Property Concentration Risk [Member] Investment Property Concentration Risk Principal Repayments and Joint Venture Debt Maturities of Long-Term Debt [Abstract] Investments in unconsolidated joint ventures Company's investments in unconsolidated joint ventures Equity Method Investments Financial Instrument [Axis] Financial Instrument [Axis] Properties Held for Sale and Property Dispositions Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Fair value of derivatives in a net liability position Derivative, Net Liability Position, Aggregate Fair Value Maximum fungible units that may be granted (in shares) Share Based Compensation Arrangement by Share Based Payment Award, Number of Fungible Units Authorized Represents the maximum number of fungible units authorized to be granted by the entity. Issuance of special dividend paid primarily in stock Issuance of special distribution paid primarily in units Issuance Of Special Dividend, Stock Dividend Issuance Of Special Dividend, Stock Dividend Repurchase of common stock Repurchase of common units Payments for Repurchase of Common Stock Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Supplemental Disclosure of Non-Cash Investing and Financing Activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Segment [Domain] Segments [Domain] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Retained earnings Retained Earnings (Accumulated Deficit) Number of portfolio segments of financial receivables (segment) Financing Receivable, Portfolio Segments Number Represents the number of portfolio segments of financing receivables. Debt instrument face amount Debt Instrument, Face Amount 2026 Future Amortization of Debt Fourth Full Fiscal Year The amount of amortization of debt expected to be recognized during the fourth full fiscal year following the date of the most recent balance sheet. 625 Madison Avenue Madison Ave, 625 [Member] Madison Ave, 625 Leases [Abstract] Leases [Abstract] Entity Address, State or Province Entity Address, State or Province Operating Activities Net Cash Provided by (Used in) Operating Activities [Abstract] Proceeds from repayment of debt marketable securities Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale Disposal Group Name [Domain] Disposal Group Name [Domain] Related party receivables Other Receivables Operating Partnership units redeemable for common shares (shares) Incremental Common Shares, Attributable to Redemption of Units to Common Shares Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of the redemption of units to common shares. Series I Preferred Units, $25.00 liquidation preference, 9,200 issued and outstanding at both September 30, 2023 and December 31, 2022 Preferred Units, Preferred Partners' Capital Accounts Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Interest rate cap and swap agreements (included in Other assets) Fair Value Derivative Asset, Subject to Master Netting Arrangement, before Offset 100 Church Street Church Street, 100 [Member] Represents the information pertaining to 100 Church Street, a property owned by the entity. Loan interest income Financing Receivable, Nonaccrual, Interest Income Class of Stock [Domain] Class of Stock [Domain] Customer [Domain] Customer [Domain] Net (loss) income attributable to SL Green common stockholders, basic (Loss) income attributable to SL Green common stockholders Net Income (Loss) Available to Common Stockholders, Basic Preferred Equity, February 2027 Preferred Equity, February 2027 [Member] Preferred Equity, February 2027 [Member] Options Outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] Name of Property [Domain] Name of Property [Domain] Operating Partnership Operating Partnership [Member] Operating Partnership [Member] Lease liability - operating leases Operating Lease, Liability Interest Rate Cap Expiring May 2024 Interest Rate Cap Expiring May 2024 [Member] Interest Rate Cap Expiring May 2024 Issuance of common units Issuance of preferred units Noncontrolling Interest, Increase from Subsidiary Equity Issuance Noncontrolling interests in other partnerships Partners' Capital Attributable to Noncontrolling Interest Organization and Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Sale Price Disposal Group, Including Discontinued Operation, Consideration Debt investment originations/fundings/accretion Debt Investments in Mortgage Loans Debt Investments in Mortgage Loans [Member] Represents debt investments in mortgage loans on real estate. Accumulated Other Comprehensive Income Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] SL Green partners' capital (685 and 680 general partner common units and 63,713 and 63,700 limited partner common units outstanding at September 30, 2023 and December 31, 2022, respectively) General And Limited Partners Capital Account General And Limited Partners Capital Account Additions to land, buildings and improvements Payments To Acquire Land, Buildings And Improvements Payments To Acquire Land, Buildings And Improvements Noncontrolling interests in other partnerships Net loss (income) attributable to noncontrolling interests Noncontrolling Interest in Net Income (Loss) Other Noncontrolling Interests, Redeemable Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Statement of Partners' Capital [Abstract] Statement of Partners' Capital [Abstract] Plan Name [Axis] Plan Name [Axis] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Number of reportable segments Number of Reportable Segments Mezzanine Loan Repaid Mezzanine Loan Repaid [Member] Mezzanine Loan Repaid Distributions to noncontrolling interests in other partnerships Distributions to Noncontrolling Interests Other Partnerships The cash outflow for distributions to the entity's partner from a consolidated joint venture. Earnings Per Share Earnings Per Share [Abstract] Common stock, $0.01 par value, 160,000 shares authorized and 65,458 and 65,440 issued and outstanding at September 30, 2023 and December 31, 2022, respectively (including 1,060 and 1,060 shares held in treasury at September 30, 2023 and December 31, 2022, respectively) Common Stock, Value, Issued Mathias Mathias [Member] Mathias Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Preferred distributions Distributions Preferred Units Distributions declared for preferred units during the period. Book value of collateral Collateral Already Posted, Aggregate Fair Value Senior Unsecured Notes Senior Notes [Member] 1185 Avenue of the Americas Avenue of the Americas, 1185 [Member] Represents the information pertaining to 1185 Avenue of the Americas, a property owned by the entity. Preferred stock, dividend, multiplier per common unit distribution Preferred Stock Dividend Multiplier Ratio Per Common Unit Distribution Preferred Stock Dividend Multiplier Ratio Per Common Unit Distribution Accrued interest payable Interest Payable Stabilization of property, anniversary period Related Party Transaction, Stabilization Of Property, Anniversary Period Related Party Transaction, Stabilization Of Property, Anniversary Period 5 Times Square Times Square, 5 [Member] Times Square, 5 Entity Filer Category Entity Filer Category General information on each joint venture Schedule of Equity Method Investments [Line Items] Investment in Unconsolidated Joint Ventures Schedule of Equity Method Investments [Line Items] Stock-based compensation plans (shares) Incremental Common Units Attributable to Share based Payment Arrangements Incremental Common Units Attributable to Share based Payment Arrangements Proceeds from mortgages and other loans payable Proceeds from Issuance of Secured Debt Class of treasury stock Class of Treasury Stock [Table Text Block] Total SLGOP partners' capital Partners' Capital Statement [Table] Statement [Table] Current Fiscal Year End Date Current Fiscal Year End Date Stock repurchase program, authorized amount Stock Repurchase Program, Authorized Amount 450 Park Avenue Park Avenue, 450 [Member] Park Avenue, 450 2023 Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year Preferred stock, shares authorized (shares) Preferred Stock, Shares Authorized RXR Realty / New York REIT RXR Realty / New York REIT [Member] RXR Realty / New York REIT Shares that may be issued if equal to fungible units (shares) (less than) Share Based Compensation Arrangement by Share Based Payment Award, Number of Shares to be Issued if Equal to Fungible Units Represents the number of shares that would be issued under the plan if shares issued is equal to fungible units; actual shares issued may be more or less depending on the type of awards issued and the ratio of fungible units to shares under each award. Building Building [Member] Junior subordinated deferrable interest debentures held by trusts that issued trust preferred securities Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust Amount of Gain Reclassified from Accumulated Other Comprehensive Income into Income Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Series R Series R Preferred Stock [Member] Series R Preferred Stock [Member] Gross amount Finite Lived Intangible Liabilities, Gross Represents the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible liabilities having statutory or estimated useful lives. Term of extension Line Of Credit Facility, Term Of Extension Line Of Credit Facility, Term Of Extension Interest expense, net of interest income Interest Expense, Other Net (loss) income Income (Loss) from Continuing Operations before Realized Gain (Loss) on Disposal of Equity Method Investment This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before realized gains (losses) on disposals of equity method investments, extraordinary items, and noncontrolling interest. Other income Profit participation from related party Other Income Thereafter Future Amortization of Debt after Fifth Full Fiscal Year The amount of amortization of debt expected to be recognized after the fifth full fiscal year following the date of the most recent balance sheet. Face Value Investment Owned, Face Amount Redemptions/sales/syndications/equity ownership/amortization SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Amortization of Premium Non-cash lease expense Non Cash Lease Expense Non Cash Lease Expense Duration of each offering period starting the first day of each calendar quarter (in months) Share Based Compensation Arrangement by Share Based Payment Award, Duration of Offering Periods Represents the duration of each offering period during which the shares are offered for purchase under the stock-based compensation plan of the entity. Coupon Rate (as a percent) Debt Instrument, Interest Rate, Stated Percentage Schedule of calculation of numerator and denominator in earnings per unit Schedule of Calculation of Numerator and Denominator in Earnings Per Unit [Table Text Block] Schedule of Calculation of Numerator and Denominator in Earnings Per Unit [Table Text Block] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Total SL Green stockholders' equity Equity, Attributable to Parent Preferred units, liquidation preference (in dollars per share) Liquidation Preference Per Unit (in dollars per share) Temporary Equity, Liquidation Preference Per Share Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Expected term Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term Fixed rate debt Long-Term Debt, Percentage Bearing Fixed Interest, Amount Other Affiliates Other Affiliates [Member] Distributions Noncontrolling Interest, Decrease from Distributions to Other Noncontrolling Interest Holders Noncontrolling Interest, Decrease from Distributions to Other Noncontrolling Interest Holders Level 2 Fair Value, Inputs, Level 2 [Member] 2022 Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year Investments difference between carrying amount and underlying equity Equity Method Investment, Difference Between Carrying Amount and Underlying Equity Issuance of special dividend paid primarily in stock Stock Issued During Period, Value, Stock Dividend Number of residential units Number Of Residential Units Number Of Residential Units Stockholders' Equity Stockholders Equity [Line Items] -- None. No documentation exists for this element. -- Schedule of effect of derivative financial instruments on consolidated statements of income Derivative Instruments, Gain (Loss) [Table Text Block] Property Interest Liquidation Property Interest Liquidation [Member] Property Interest Liquidation Increase (Decrease) in Stockholders' Equity Increase (Decrease) in Partner's Capital Increase (Decrease) in Stockholders' Equity [Roll Forward] Investment in joint venture, ownership percentage Investment In Joint Venture, Ownership Percentage Investment In Joint Venture, Ownership Percentage Stabilization of property, within three years after stabilization, percent Related Party Transaction, Stabilization Of Property, Within Three Years After Stabilization, Percent Related Party Transaction, Stabilization Of Property, Within Three Years After Stabilization, Percent Document Fiscal Period Focus Document Fiscal Period Focus Estimated useful life of other intangible assets (in years) Finite-Lived Intangible Asset, Useful Life Total expenses Total Costs and Expenses Including Nonoperating Income (Expense) This element represents the total of the costs related to real estate revenues, including management, leasing, and development services and income (expense) from ancillary business-related activities. Ability to borrow under line of credit facility Line of Credit Facility, Remaining Borrowing Capacity Balance at beginning of year (in dollars per share) Balance at end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Weighted Average Weighted Average [Member] Series W Series W Preferred Stock [Member] Series W Preferred Stock [Member] City Area Code City Area Code Product and Service [Axis] Product and Service [Axis] Financial Asset, Period Past Due [Domain] Financial Asset, Aging [Domain] Joint venture Corporate Joint Venture [Member] Number of financing receivables on non-accrual without allowance for loan loss Financing Receivable, Nonaccrual, No Allowance, Number Financing Receivable, Nonaccrual, No Allowance, Number Investment in joint venture aggregate maximum ownership percentage Investment In Joint Venture Aggregate Maximum Ownership Percentage Investment In Joint Venture Aggregate Maximum Ownership Percentage Ownership Interest Ownership Interest Disposed Equity Method Investment, Ownership Percentage Document Fiscal Year Focus Document Fiscal Year Focus SL Green Management LLC SLG Management LLC [Member] SLG Management LLC [Member] Net (loss) income attributable to SLGOP common unitholders (numerator for basic earnings per unit) Net Income (Loss) Available To Common Stockholders, After Distributed And Undistributed Earnings Allocation, Basic Net Income (Loss) Available To Common Stockholders, After Distributed And Undistributed Earnings Allocation, Basic One Vanderbilt Avenue One Vanderbilt [Member] One Vanderbilt [Member] Debt and preferred equity investments Debt And Preferred Equity Reserves Debt And Preferred Equity Reserves Maximum borrowing capacity, optional expansion Line of Credit Facility, Optional Expansion, Maximum Borrowing Capacity The expanded maximum borrowing capacity available, which is subject to agreement with the entity. Share Repurchase Program [Domain] Share Repurchase Program [Domain] Carrying value of investment in leasehold interest SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Gross Number of investments, nonperforming Number Of Investments, Nonperforming Number Of Investments, Nonperforming Total capital Beginning balance Ending balance Partners' Capital, Including Portion Attributable to Noncontrolling Interest Summary of the status of stock options and changes during the period Share-Based Payment Arrangement, Option, Activity [Table Text Block] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Schedule of Preferred Units [Table] Schedule of Preferred Units [Table] Period of extension options Debt Instrument, Period of Extension Option Debt Instrument, Period of Extension Option Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Schedule of first mortgages and other loans payable collateralized by the respective properties and assignment of leases Mortgage And Other Loans Payable [Table Text Block] Mortgage And Other Loans Payable [Table Text Block] Interest Rate Swap Expiring in February 2027 Interest Rate Swap Expiring in February 2027 [Member] Interest Rate Swap Expiring in February 2027 10 East 53rd Street East 53rd Street 10 [Member] Represents information pertaining to 10 East 53rd Street, a joint venture property of the entity. Series V Series V Preferred Stock [Member] Series V Preferred Stock [Member] Number of buildings Number of Buildings Number of Real Estate Buildings Number of Real Estate Buildings Net (loss) income Net (loss) income Net loss Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Aggregate weighted average current yield (as a percent) SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Interest Rate Accumulated amortization Finite Lived Intangible Liabilities, Accumulated Amortization Represents the accumulated amount of amortization of a major finite-lived intangible liability class. Total liabilities and equity/capital Liabilities and Equity Ownership [Domain] Ownership [Domain] Right of use asset - operating leases Operating Lease, Right-of-Use Asset Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Schedule of noncontrolling interest Schedule of Noncontrolling Interest [Table Text Block] Tabular disclosure of the information pertaining to the noncontrolling interest. Debt Investment, Two Debt Investment, Two [Member] Debt Investment, Two Net (loss) income attributable to SL Green common stockholders, diluted Net Income (Loss) Available to Common Stockholders, Diluted Percentage of profits due to investors (as a percentage) Related Party Transaction, Percentage of Profits Due to Investors Related Party Transaction, Percentage of Profits Due to Investors 15 Beekman Beekman, 15 [Member] Beekman, 15 Period of commencement of option vesting, from date of grant (in years) Share Based Compensation Arrangement by Share Based Payment Award, Period of Award Vesting Commencement Represents the period from the date of grant of the awards for the commencement of vesting of awards. Entity Address, City or Town Entity Address, City or Town Schedule of selected results of operations and selected asset information Schedule of Segment Reporting Information, by Segment [Table Text Block] Related Party Related Party [Member] Partner Capital Components [Axis] Partner Capital Components [Axis] Deferred rents receivable Straight Line Rent Worldwide Plaza Worldwide Plaza [Member] Worldwide Plaza [Member] Mezzanine Loan With Initial Maturity Date of December 2029 Mezzanine Loan With Initial Maturity Date Of December 2029 [Member] Mezzanine Loan With Initial Maturity Date Of December 2029 [Member] 2 Herald Square 2 Herald Square Herald Square, 2 [Member] 2 Herald Square [Member] Fair Value Measurements Fair Value of Financial Instruments, Policy [Policy Text Block] Acquisition of subsidiary interest from noncontrolling interest Redemption and conversion of common units Redemption of preferred units Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Real Estate by Location [Axis] Real Estate by Location [Axis] Represents details pertaining to the locations of real estate properties of the entity. Proceeds from sale or redemption of marketable securities Proceeds from Sale and Maturity of Marketable Securities Common stock, shares authorized (in shares) Common Stock, Shares Authorized Construction Loans Construction Loans [Member] Document Information [Table] Document Information [Table] 4.27% Senior unsecured notes maturing on December 17, 2025 Senior Unsecured Note Due December 17, 2025 [Member] Senior Unsecured Note Due December 17, 2025 [Member] Financial Asset, Period Past Due [Axis] Financial Asset, Aging [Axis] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate Schedule [Table] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate Schedule [Table] Deferred leasing costs Deferred Costs, Leasing, Gross Excess stock, par value (in dollars per share) Excess Stock, Par or Stated Value Per Share Face amount or stated value of excess stock per share, which is generally not indicative of the fair market value per share. Mortgages and other loans payable Mortgage and Other Loans Payable [Member] Represents mortgage and other loans payable of the entity. Related Party Transactions [Abstract] Related Party Transactions [Abstract] 2024 Future Amortization of Debt, Second Full Fiscal Year The amount of amortization of debt expected to be recognized during the second full fiscal year following the date of the most recent balance sheet. East 21 Street 66, 1 East 21 Street 66, 1 [Member] East 21 Street 66, 1 Financial Instruments: Derivatives and Hedging Derivative [Line Items] Conversion of stock, shares issued Conversion of Stock, Shares Issued Issuance of special distribution paid primarily in units (in shares) Unit Dividends, Units Unit Dividends, Units Debt and preferred equity investments, net of discounts and deferred origination fees of $1,638 and $1,811 and allowances of $13,520 and $6,630 in 2023 and 2022, respectively Carrying Value Debt and preferred equity investments Mortgage Loans on Real Estate, Commercial and Consumer, Net Partnership Interest Partnership Interest [Member] Dividend and distributions payable Dividends Payable PGIM Real Estate PGIM Real Estate [Member] PGIM Real Estate Debt and preferred equity investments and other financing receivables included in other balance sheet items Debt Investments, Other Debt Investments, Other Fair value of restricted stock vested during the period Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Additional paid-in-capital Additional Paid in Capital Fair value adjustment Minority Interest Increase (Decrease) from Fair Value Adjustment Represents the increase (decrease) in noncontrolling interest resulting from fair value adjustments. Recorded investment, past due Carrying value Carrying Value, Fixed Rate Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss Document Information [Line Items] Document Information [Line Items] 2016 Repurchase Program 2016 Repurchase Program [Member] 2016 Repurchase Program [Member] Basic (loss) earnings per unit (in dollars per share) Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax Investment in Commercial Real Estate Properties Investment in Real Estate [Policy Text Block] Disclosure of accounting policy for investments in real estate properties. Income Taxes Income Tax, Policy [Policy Text Block] Schedule of combined statements of income for the unconsolidated joint ventures Equity Method Investments, Summarized Financial Information Income Statement [Table Text Block] Disclosure of summarized income statement information for investments accounted for using the equity method of accounting. Loss on Sale Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax Accrued dividends on preferred units Noncontrolling Interest, Accrued Dividends On Preferred Units Noncontrolling Interest, Accrued Dividends On Preferred Units Related Party [Axis] Related Party, Type [Axis] Purchase price and other fair value adjustments Gain (Loss) On Purchase Price Fair Value Adjustment Gross The impact of fair value adjustments on purchase price and it's impact on net income or loss for the period, gross. Debt instrument, face amount, increase limit Debt Instrument, Face Amount, Limit Increase Debt Instrument, Face Amount, Limit Increase Entity Registrant Name Entity Registrant Name Depreciable real estate reserves and impairment Depreciable Real Estate Reserves, Cash Flow Effect Depreciable Real Estate Reserves, Cash Flow Effect Other assets Increase (Decrease) in Other Operating Assets Amount participated out Mortgage Loans on Real Estate Loan Value Represents the amount of loan participation on property mortgage. SLGOP partners' capital: Partners' Capital [Abstract] Stated Distribution Rate Preferred stock, distribution rate Preferred Stock, Dividend Rate, Percentage Disposal Group Name [Axis] Disposal Group Name [Axis] Options exercisable at end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price Preferred Units [Line Items] Preferred Units [Line Items] Accreted Balance, net of deferred financing costs Senior Notes, Net of Deferred Finance Costs Senior Notes, Net of Deferred Finance Costs Entity Central Index Key Entity Central Index Key Basis spread on variable rate Loans Receivable, Basis Spread on Variable Rate Unconsolidated Unconsolidated Properties [Member] Compensation expense Share-Based Payment Arrangement, Expense Series S Series S Preferred Stock [Member] Series S Preferred Stock [Member] Gross amount Finite-Lived Intangible Assets, Gross 115 Spring Street 115 Spring Street Spring Street 115 [Member] Spring Street 115 [Member] Mezzanine Loan Due April 2023 Mezzanine Loan Due April 2023 [Member] Mezzanine Loan Due April 2023 220 East 42nd Street East 220 Street 42 [Member] Represents the information pertaining to 220 East 42nd Street, a property owned by the entity. Other comprehensive income Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Depreciable real estate reserves and impairment Depreciable Real Estate Reserves, Effect on Earnings Depreciable Real Estate Reserves, Effect on Earnings Interest Rate Cap Expiring May 2024, 2 Interest Rate Cap Expiring May 2024, 2 [Member] Interest Rate Cap Expiring May 2024, 2 Consolidated Consolidated Properties [Member] Entity [Domain] Entity [Domain] Commercial properties Commercial Property [Member] Commercial Property [Member] Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Amendment Flag Amendment Flag Preferred units, shares outstanding (in shares) Number of Units Outstanding (in shares) Temporary Equity, Shares Outstanding Legal Entity [Axis] Legal Entity [Axis] Thereafter Long Term Debt, Maturity, After Year Four Long Term Debt, Maturity, After Year Four Mezzanine Loan Repaid - 2 Mezzanine Loan Repaid2 [Member] Mezzanine Loan Repaid2 Unsecured term loans, net Accreted Balance Senior Notes Interest expense, net Interest Income (Expense), Net Fair value adjustment to noncontrolling interest in the Operating Partnership Operating Partnership Noncontrolling Interest Fair Value Adjustment Represents the fair value adjustment to the noncontrolling interest in the operating partnership. Maximum percentage of annualized rent for any one tenant not individually disclosed (percent) (more than) Concentration Risk Percentage Threshold Represents the maximum percentage of concentration risk that is not individually disclosed. Preferred units, shares issued (in shares) Number of Units Issued (in shares) Temporary Equity, Shares Issued Rollforward Analysis of Preferred Unit Activity Rollforward Analysis of Preferred Unit Activity [Roll Forward] Rollforward Analysis of Preferred Unit Activity [Roll Forward] Provision for loan loss related to an investment originated prior to 2021 Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff Annual award vesting rate, low end of range (as a percent) Share Based Compensation Arrangement by Share Based Payment Award, Award Vesting Rate, Low End of Range Represents the low end of the range of annual vesting rates that occurs once performance criteria are reached. Diluted weighted average common shares and common share equivalents outstanding (in shares) Diluted weighted average common stock outstanding (shares) Weighted Average Number of Shares Outstanding, Diluted Term Loan 2022 Term Loan 2022 [Member] Term Loan 2022 21 East 66th Street 21 East 66th Street East 21 Street 66 [Member] Represents the information pertaining to 21 East 66th Street, a joint venture property of the entity. Amortization of acquired above and below-market leases Amortization of above and below Market Leases Summary of properties sold Disposal Groups, Including Discontinued Operations [Table Text Block] Number of real estate properties acquired from third party Number Of Real Estate Properties Acquired From Third Party Number Of Real Estate Properties Acquired From Third Party Vornado Realty Trust Vornado Realty Trust [Member] Vornado Realty Trust Variable lease payments Operating Lease, Variable Lease Income East 21 Street 66, 2 East 21 Street 66, 2 [Member] East 21 Street 66, 2 RXR Realty Led Investment Group RXR Realty Led Investment Group [Member] RXR Realty Led Investment Group A Fund Affiliated With Winthrop Capital Partners Private Investor [Member] Private Investor Above-market leases Above Market Leases [Member] Total assets Total assets Assets Share Repurchase Program [Axis] Share Repurchase Program [Axis] Series A Series A Preferred Stock [Member] Debt Investment [Axis] Debt Investment [Axis] Debt Investment Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Preferred units Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount 100 Park Avenue Park Avenue, 100 [Member] Represents the information pertaining to 100 Park Avenue, a joint venture property of the entity. Investments in marketable securities Total investment in marketable securities Marketable Securities Interest on financing leases Finance Lease, Interest Expense, Before Capitalized Interest Finance Lease, Interest Expense, Before Capitalized Interest Mortgage Investment One Mortgage Investment One [Member] Mortgage Investment One 690 Madison Avenue 690 Madison Avenue [Member] 690 Madison Avenue Debt Instrument [Line Items] Corporate Indebtedness Debt Instrument [Line Items] 11 Madison Avenue Madison Ave, 11 [Member] 11 Madison Ave [Member] Basic weighted average common shares outstanding (in shares) Weighted average common shares outstanding (shares) Weighted Average Number of Shares Outstanding, Basic Interest income Sales-type Lease, Interest Income Schedule of Property, Plant and Equipment and Finite Lived Intangible Assets and Liabilities, by Major Class [Table] Schedule of Property, Plant and Equipment and Finite Lived Intangible Assets and Liabilities, by Major Class [Table] Table of long-lived, physical assets and finite lived intangible assets and liabilities that are used in the normal conduct of business to produce goods and services and which are not intended for resale. Commercial real estate properties, at cost: Real Estate Investment Property, at Cost [Abstract] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Financing receivable on non-accrual without allowance Financing Receivable, Nonaccrual, No Allowance Revenues Revenues [Abstract] Term Loan B, Maturity November 2024 Term Loan B, Maturity November 2024 [Member] Term Loan B, Maturity November 2024 [Member] 919 Third Avenue Third Avenue, 919 [Member] Represents the information pertaining to 919 Third Avenue, a property owned by the entity. Rental revenue, net Rental revenue, net Total rental revenue Operating Lease, Lease Income Related Party Transaction [Axis] Related Party Transaction [Axis] Statement [Line Items] Statement [Line Items] Wharton Properties / Private Investor Wharton Properties / Private Investor [Member] Wharton Properties / Private Investor Concentration Risk [Table] Concentration Risk [Table] Schedule of notional and fair value of derivative financial instruments and foreign currency hedges Schedule of Derivative Instruments [Table Text Block] Interest Rate Swap Expiring in November 2023 Interest Rate Swap Expiring in November 2023 [Member] Interest Rate Swap Expiring in November 2023 Balance at beginning of period Balance at end of period Noncontrolling Interest in Operating Partnerships Schedule of debt Schedule of Debt [Table Text Block] All other awards Other Awards [Member] Represents awards granted by the entity that deliver the full value of the award upon vesting. Schedule of marketable securities Debt Securities, Available-for-Sale [Table Text Block] Name of Property [Axis] Name of Property [Axis] Noncontrolling Interests Noncontrolling Interest [Member] Total principal repayments Long Term Debt, Maturities, Repayments of Principal Total amount of long-term debt maturing in future periods.