Investments in Unconsolidated Joint Ventures - Acquisition, Development and Construction Arrangements/Sale of Joint Venture Interest or Property (Details) - USD ($)	1 Months Ended						12 Months Ended
	Apr. 30, 2022	Sep. 30, 2021	Jun. 30, 2021	Apr. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
(Loss) Gain on Sale							$ (131,000)	$ (32,757,000)	$ 2,961,000
Employee-related liabilities						$ 0	$ 0	$ 1,400,000	$ 0
East 400 47th Street
Schedule of Equity Method Investments [Line Items]
Asset impairment loss				$ 5,700,000
Joint venture | East 400 47th 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)
Joint venture | 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
Joint venture | 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)
Joint venture | 333 East 22nd Street | Various Partners
Schedule of Equity Method Investments [Line Items]
Ownership Interest Sold						33.33%			33.33%
Gross Asset Valuation						$ 1,600,000			$ 1,600,000
(Loss) Gain on Sale						$ 3,000,000.0
Joint venture | Stonehenge Portfolio
Schedule of Equity Method Investments [Line Items]
Gross Asset Valuation	$ 1,000,000.0
(Loss) Gain on Sale	$ 0