Investments in Unconsolidated Joint Ventures - Schedule of Mortgage Notes and Other Loans Payable Collateralized by the Respective Joint Venture Properties and Assignment of Leases (Details) - USD ($)
$ in Thousands

Investments in Unconsolidated Joint Ventures - Schedule of Mortgage Notes and Other Loans Payable Collateralized by the Respective Joint Venture Properties and Assignment of Leases (Details) - USD ($) $ in Thousands	Oct. 31, 2026	Sep. 30, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Total fixed rate debt		$ 2,159,386	$ 2,075,222
Total floating rate debt		57,413	79,277
Due from joint ventures
Debt Instrument [Line Items]
Total fixed rate debt		12,387,080	10,791,783
Total floating rate debt		500,435	1,687,249
Total fixed rate and floating rate debt		12,887,515	12,479,032
Deferred financing costs, net		(98,473)	(100,882)
Total joint venture mortgages and other loans payable, net		12,789,042	12,378,150
Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		5,806,311	5,415,627
Total floating rate debt		177,899	481,571
Total fixed rate and floating rate debt		5,984,210	5,897,198
Deferred financing costs, net		(47,305)	(50,476)
Total joint venture mortgages and other loans payable, net		$ 5,936,905	5,846,722
650 Fifth Avenue \| Wharton Properties \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		50.00%
Interest rate, fixed rate debt (as a percent)		5.45%
Total fixed rate debt		$ 65,000	65,000
Interest rate, floating rate debt (as a percent)		2.25%
Total floating rate debt		$ 210,000	210,000
650 Fifth Avenue \| Wharton Properties \| Due from joint ventures \| Subsequent Event
Debt Instrument [Line Items]
Extinguishment of secured debt, bearing fixed interest, amount	$ 65,000
Secured debt, bearing fixed interest, mezzanine loan amount	2,000
650 Fifth Avenue \| Wharton Properties \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		32,500	32,500
Total floating rate debt		$ 105,000	105,000
1515 Broadway \| Private Investor \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		56.87%
Interest rate, fixed rate debt (as a percent)		3.93%
Total fixed rate debt		$ 666,175	718,949
1515 Broadway \| Private Investor \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 378,847	408,859
919 Third Avenue \| Vornado Realty Trust \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		51.00%
Interest rate, fixed rate debt (as a percent)		6.41%
Total fixed rate debt		$ 500,000	500,000
919 Third Avenue \| Vornado Realty Trust \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 255,000	255,000
245 Park Avenue \| Allianz Real Estate of America \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		50.10%
Interest rate, fixed rate debt (as a percent)		4.30%
Total fixed rate debt		$ 1,768,000	1,768,000
245 Park Avenue \| Allianz Real Estate of America \| Due from joint ventures \| Subsequent Event
Debt Instrument [Line Items]
Total fixed rate debt	$ 2,000,000
Fixed interest term	5 years
245 Park Avenue \| Allianz Real Estate of America \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 885,768	885,768
115 Spring Street \| New York State Teacher's Retirement System \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		51.00%
Interest rate, fixed rate debt (as a percent)		5.50%
Total fixed rate debt		$ 66,621	65,550
115 Spring Street \| New York State Teacher's Retirement System \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 33,977	33,431
280 Park Avenue \| U.S. Affiliate of Mori Trust Co., Ltd \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		50.00%
Interest rate, fixed rate debt (as a percent)		5.84%
Total fixed rate debt		$ 1,075,000	1,075,000
280 Park Avenue \| U.S. Affiliate of Mori Trust Co., Ltd \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 537,500	537,500
Worldwide Plaza \| RXR Realty / New York REIT \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		25.05%
Interest rate, fixed rate debt (as a percent)		3.98%
Total fixed rate debt		$ 1,200,000	1,200,000
Worldwide Plaza \| RXR Realty / New York REIT \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 300,600	300,600
220 East 42nd Street \| A fund managed by Meritz Alternative Investment Management \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		51.00%
Interest rate, fixed rate debt (as a percent)		6.77%
Total fixed rate debt		$ 496,412	496,412
220 East 42nd Street \| A fund managed by Meritz Alternative Investment Management \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 253,170	253,170
100 Park Avenue \| Rockpoint Capital \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		50.80%
Interest rate, fixed rate debt (as a percent)		5.73%
Total fixed rate debt		$ 382,872	382,872
100 Park Avenue \| Rockpoint Capital \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 194,499	194,499
15 Beekman \| A fund managed by Meritz Alternative Investment Management \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		20.00%
Interest rate, fixed rate debt (as a percent)		4.83%
Total fixed rate debt		$ 117,000	120,000
15 Beekman \| A fund managed by Meritz Alternative Investment Management \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 23,400	24,000
11 Madison Avenue \| PGIM Real Estate \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		60.00%
Interest rate, fixed rate debt (as a percent)		5.62%
Total fixed rate debt		$ 1,400,000	1,400,000
11 Madison Avenue \| PGIM Real Estate \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 840,000	840,000
One Madison Avenue \| National Pension Service of Korea / Hines Interest LP / International Investor \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		25.50%
Interest rate, fixed rate debt (as a percent)		5.81%
Total fixed rate debt		$ 1,650,000	0
Total floating rate debt		0	1,163,814
One Madison Avenue \| National Pension Service of Korea / Hines Interest LP / International Investor \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		420,750	0
Total floating rate debt		$ 0	296,772
One Vanderbilt Avenue \| National Pension Service of Korea / Hines Interest LP / Mori Building Co., Ltd \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		55.01%
Interest rate, fixed rate debt (as a percent)		2.95%
Total fixed rate debt		$ 3,000,000	3,000,000
One Vanderbilt Avenue \| National Pension Service of Korea / Hines Interest LP / Mori Building Co., Ltd \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total fixed rate debt		$ 1,650,300	1,650,300
450 Park Avenue \| Korean Institutional Investor / Israeli Institutional Investor \| Due from joint ventures
Debt Instrument [Line Items]
Economic interest (as a percent)		25.10%
Interest rate, floating rate debt (as a percent)		2.10%
Total floating rate debt		$ 290,435	290,435
450 Park Avenue \| Korean Institutional Investor / Israeli Institutional Investor \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total floating rate debt		72,899	72,899
11 West 34th Street \| Private Investor / Wharton Properties \| Due from joint ventures
Debt Instrument [Line Items]
Total floating rate debt		0	23,000
11 West 34th Street \| Private Investor / Wharton Properties \| Due from joint ventures \| Common Stock
Debt Instrument [Line Items]
Total floating rate debt		$ 0	$ 6,900