Revenue Recognition (Revenues by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disaggregation of Revenue [Line Items]
Lease income	$ 403,835	$ 388,891	$ 785,712	$ 771,922
Total revenues	$ 472,359	$ 453,494	$ 918,282	$ 895,624
Operating Lease, Lease Income, Statement of Income or Comprehensive Income [Extensible Enumeration]	Total revenues	Total revenues	Total revenues	Total revenues
Loss contingency, damages awarded, value	$ 21,350		$ 21,350
Noncontrolling Interest
Disaggregation of Revenue [Line Items]
Loss contingency, damages awarded, value	6,405		6,405
New York
Disaggregation of Revenue [Line Items]
Total revenues	362,471	$ 364,162	726,285	$ 722,710
Other
Disaggregation of Revenue [Line Items]
Total revenues	109,888	89,332	191,997	172,914
Rental revenues
Disaggregation of Revenue [Line Items]
Total revenues	418,834	405,194	815,627	802,477
Rental revenues | New York
Disaggregation of Revenue [Line Items]
Total revenues	316,702	322,040	636,218	640,885
Rental revenues | Other
Disaggregation of Revenue [Line Items]
Total revenues	102,132	83,154	179,409	161,592
Lease revenues
Disaggregation of Revenue [Line Items]
Lease income	403,835	388,891	785,712	771,922
Lease revenues | New York
Disaggregation of Revenue [Line Items]
Lease income	305,182	309,882	612,904	617,605
Lease revenues | Other
Disaggregation of Revenue [Line Items]
Lease income	98,653	79,009	172,808	154,317
Property rentals
Disaggregation of Revenue [Line Items]
Lease income	397,053	383,049	773,882	760,936
Property rentals | New York
Disaggregation of Revenue [Line Items]
Lease income	305,182	309,882	612,904	617,605
Property rentals | Other
Disaggregation of Revenue [Line Items]
Lease income	91,871	73,167	160,978	143,331
Trade shows
Disaggregation of Revenue [Line Items]
Lease income	6,782	5,842	11,830	10,986
Trade shows | New York
Disaggregation of Revenue [Line Items]
Lease income	0	0	0	0
Trade shows | Other
Disaggregation of Revenue [Line Items]
Lease income	6,782	5,842	11,830	10,986
Tenant services
Disaggregation of Revenue [Line Items]
Revenue	9,804	11,461	19,573	21,350
Tenant services | New York
Disaggregation of Revenue [Line Items]
Revenue	7,325	8,133	14,907	15,544
Tenant services | Other
Disaggregation of Revenue [Line Items]
Revenue	2,479	3,328	4,666	5,806
Parking revenues
Disaggregation of Revenue [Line Items]
Revenue	5,195	4,842	10,342	9,205
Parking revenues | New York
Disaggregation of Revenue [Line Items]
Revenue	4,195	4,025	8,407	7,736
Parking revenues | Other
Disaggregation of Revenue [Line Items]
Revenue	1,000	817	1,935	1,469
Fee and other income
Disaggregation of Revenue [Line Items]
Revenue	53,525	48,300	102,655	93,147
Total revenues	53,525	48,300	102,655	93,147
Fee and other income | New York
Disaggregation of Revenue [Line Items]
Revenue	45,769	42,122	90,067	81,825
Fee and other income | Other
Disaggregation of Revenue [Line Items]
Revenue	7,756	6,178	12,588	11,322
BMS cleaning fees
Disaggregation of Revenue [Line Items]
Revenue	35,146	33,999	70,474	66,690
BMS cleaning fees | New York
Disaggregation of Revenue [Line Items]
Revenue	37,754	36,206	75,432	70,917
BMS cleaning fees | Other
Disaggregation of Revenue [Line Items]
Revenue	(2,608)	(2,207)	(4,958)	(4,227)
Management and leasing fees
Disaggregation of Revenue [Line Items]
Revenue	3,658	2,866	6,707	5,635
Management and leasing fees | New York
Disaggregation of Revenue [Line Items]
Revenue	3,761	3,011	6,934	5,978
Management and leasing fees | Other
Disaggregation of Revenue [Line Items]
Revenue	(103)	(145)	(227)	(343)
Other income
Disaggregation of Revenue [Line Items]
Revenue	14,721	11,435	25,474	20,822
Other income | New York
Disaggregation of Revenue [Line Items]
Revenue	4,254	2,905	7,701	4,930
Other income | Other
Disaggregation of Revenue [Line Items]
Revenue	$ 10,467	$ 8,530	$ 17,773	$ 15,892