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Properties Held for Sale and Property Dispositions - Schedule of Properties Sold (Details) | 1 Months Ended | 12 Months Ended
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Dec. 31, 2024 USD ($) ft² | Jul. 31, 2024 USD ($) ft² | Jun. 30, 2024 USD ($) ft² | Jun. 30, 2023 USD ($) ft² | Dec. 31, 2022 USD ($) ft² | Jun. 30, 2022 USD ($) ft² | May 31, 2022 USD ($) ft² | Apr. 30, 2022 USD ($) ft² | Feb. 28, 2022 USD ($) ft² | Dec. 31, 2024 USD ($) ft² | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) ft²
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Employee-related liabilities | $ 16,800,000 |  |  |  | $ 0 |  |  |  |  | $ 16,800,000 | $ 2,000,000 | $ 0
Discontinued Operation, Gain (Loss) On Disposal, Statement Of Income Or Comprehensive Income, Extensible Enumeration, Not Disclosed Flag |  |  |  |  |  |  |  |  |  | investment dispositions | investment dispositions | investment dispositions
Ownership percentage deconsolidated |  |  |  | 50.10% |  |  |  |  |  |  |  |
Investment fair value adjustment |  |  |  | $ 17,000,000 |  |  |  |  |  |  | $ 17,000,000 |
885 Third Avenue |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  |  |  |  | 218,796 |  |  |  |  |  |  | 218,796
Giorgio Armani Residences at 760 Madison Avenue (3 Condominium Units) (3) |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² | 13,590 |  |  |  |  |  |  |  |  | 13,590 |  |
Sales price | $ 63,500,000 |  |  |  |  |  |  |  |  | $ 63,500,000 |  |
(Loss) Gain on Sale | (1,500,000) |  |  |  |  |  |  |  |  |  |  |
Palisades Premier Conference Center |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  | 450,000 |  |  |  |  |  |  |  |  |  |
Sales price |  | $ 26,300,000 |  |  |  |  |  |  |  |  |  |
(Loss) Gain on Sale |  | $ 7,300,000 |  |  |  |  |  |  |  |  |  |
719 Seventh Avenue |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  |  | 10,040 |  |  |  |  |  |  |  |  |
Sales price |  |  | $ 30,500,000 |  |  |  |  |  |  |  |  |
(Loss) Gain on Sale |  |  | $ (2,000,000.0) |  |  |  |  |  |  |  |  |
245 Park Avenue |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  |  |  | 1,782,793 |  |  |  |  |  |  |  |
Sales price |  |  |  | $ 1,995,000,000 |  |  |  |  |  |  |  |
(Loss) Gain on Sale |  |  |  | $ (28,300,000) |  |  |  |  |  |  |  |
Ownership interest disposed |  |  |  | 49.90% |  |  |  |  |  |  |  |
885 Third Avenue |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  |  |  |  | 414,317 |  |  |  |  |  |  | 414,317
Sales price |  |  |  |  | $ 300,400,000 |  |  |  |  |  |  | $ 300,400,000
(Loss) Gain on Sale |  |  |  |  | (24,000,000.0) |  |  |  |  |  |  |
609 Fifth Avenue |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  |  |  |  |  | 138,563 |  |  |  |  |  |
Sales price |  |  |  |  |  | $ 100,500,000 |  |  |  |  |  |
(Loss) Gain on Sale |  |  |  |  |  | $ (80,200,000) |  |  |  |  |  |
1591-1597 Broadway |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  |  |  |  |  |  | 7,684 |  |  |  |  |
Sales price |  |  |  |  |  |  | $ 121,000,000.0 |  |  |  |  |
(Loss) Gain on Sale |  |  |  |  |  |  | $ (4,500,000) |  |  |  |  |
1080 Amsterdam Avenue |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  |  |  |  |  |  |  | 85,250 |  |  |  |
Sales price |  |  |  |  |  |  |  | $ 42,700,000 |  |  |  |
(Loss) Gain on Sale |  |  |  |  |  |  |  | $ 17,900,000 |  |  |  |
707 Eleventh Avenue |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Unaudited Approximate Usable Square Feet | ft² |  |  |  |  |  |  |  |  | 159,720 |  |  |
Sales price |  |  |  |  |  |  |  |  | $ 95,000,000.0 |  |  |
(Loss) Gain on Sale |  |  |  |  |  |  |  |  | $ (800,000) |  |  |
Properties Sold in 2023, 2022, and 2021 |  |  |  |  |  |  |  |  |  |  |  |
Property Dispositions and Assets Held for Sale |  |  |  |  |  |  |  |  |  |  |  |
Employee-related liabilities | $ 5,100,000 |  |  |  | $ 11,200,000 |  |  |  |  | $ 5,100,000 | $ 11,300,000 | $ 11,200,000

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