Investments in Partially Owned Entities (Schedule of Investments) (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities	$ 2,599,134	$ 2,610,558
Other liabilities
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities	$ (84,059)	(81,229)
Fifth Avenue and Times Square JV
Schedule Of Equity Method Investments
Interest	51.50%
Carrying amount of investments in partially owned entities	$ 2,241,278	2,242,972
Partially owned office buildings/land
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities	$ 110,224	118,558
Alexander's
Schedule Of Equity Method Investments
Interest	32.40%
Carrying amount of investments in partially owned entities	$ 85,260	87,510
Other investments
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities	$ 162,372	161,518
7 West 34th Street
Schedule Of Equity Method Investments
Interest	53.00%
7 West 34th Street | Other liabilities
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities	$ (70,207)	(69,899)
85 Tenth Avenue
Schedule Of Equity Method Investments
Interest	49.90%
85 Tenth Avenue | Other liabilities
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities	$ (13,852)	$ (11,330)