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