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Organization and Basis of Presentation - Narrative (Details) ft² in Millions, $ in Millions | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jan. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) ft² building shares | Dec. 31, 2023
Organization |  |  |
Number of shares to be received on redemption of one unit of limited partnership interests (shares) | shares |  | 1 |
Subsequent Event | Mortgage To Finance Acquisition |  |  |
Organization |  |  |
Debt instrument, face amount | $ 80.0 |  |
Initial Term (in Years) | 5 years |  |
Interest rate added to base rate (as a percent) | 2.40% |  |
Interest rate, fixed rate debt (as a percent) | 6.57% |  |
Park Avenue 500 | Subsequent Event |  |  |
Organization |  |  |
Gross Asset Valuation (in millions) | $ 130.0 |  |
Managed Office Properties |  |  |
Organization |  |  |
Approximate square feet | ft² |  | 0.4 |
Debt and preferred equity investments including investments held by unconsolidated joint ventures |  | $ 303.7 |
Debt and preferred equity investments and other financing receivables included in other balance sheet items |  | $ 9.7 |
Office |  |  |
Organization |  |  |
Number of Buildings | building |  | 1 |
Retail building |  |  |
Organization |  |  |
Number of Buildings | building |  | 1 |
Service Corporation |  |  |
Organization |  |  |
Percentage of ownership in SL Green Management LLC owned by operating partnership (percent) |  | 95.00% |
SLG Management LLC | SL Green Management |  |  |
Organization |  |  |
Percentage of ownership in SL Green Management LLC owned by operating partnership (percent) |  | 100.00% |
Operating Partnership | SL Green Operating Partnership |  |  |
Organization |  |  |
Noncontrolling interest in the operating partnership (as a percent) |  | 5.97% | 5.75%

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