Schedule III - Real Estate and Accumulated Depreciation (Details) $ in Thousands	Dec. 31, 2023 USD ($) ft²	Dec. 31, 2022 USD ($) ft²	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	$ 1,497,386
Initial Cost
Land	1,210,669
Building & Improvements	4,495,893
Cost Capitalized Subsequent To Acquisition
Land	(117,996)
Building & Improvements	1,467,536
Gross Amount at Which Carried at Close of Period
Land	1,092,671
Building & Improvements (3)	5,963,429
Total	7,056,100	$ 9,198,799	$ 7,650,907	$ 7,355,079
Accumulated Depreciation	$ 2,035,311	$ 2,039,554	$ 1,896,199	$ 1,956,077
Approximate Square Feet | ft²	29,695,841
885 Third Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	$ 0
Initial Cost
Land	138,444
Building & Improvements	244,040
Cost Capitalized Subsequent To Acquisition
Land	(138,444)
Building & Improvements	(125,747)
Gross Amount at Which Carried at Close of Period
Land	0
Building & Improvements (3)	118,293
Total	118,293
Accumulated Depreciation	11,040
Approximate Square Feet | ft²		218,796
420 Lexington Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	277,238
Initial Cost
Land	0
Building & Improvements	333,499
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	242,766
Gross Amount at Which Carried at Close of Period
Land	0
Building & Improvements (3)	576,265
Total	576,265
Accumulated Depreciation	227,258
711 Third Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	19,844
Building & Improvements	115,769
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	72,821
Gross Amount at Which Carried at Close of Period
Land	19,844
Building & Improvements (3)	188,590
Total	208,434
Accumulated Depreciation	91,897
555 West 57th Street
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	18,846
Building & Improvements	140,946
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	12,521
Gross Amount at Which Carried at Close of Period
Land	18,846
Building & Improvements (3)	153,467
Total	172,313
Accumulated Depreciation	98,508
461 Fifth Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	0
Building & Improvements	88,276
Cost Capitalized Subsequent To Acquisition
Land	28,873
Building & Improvements	12,680
Gross Amount at Which Carried at Close of Period
Land	28,873
Building & Improvements (3)	100,956
Total	129,829
Accumulated Depreciation	45,700
750 Third Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	51,093
Building & Improvements	251,523
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	83,936
Gross Amount at Which Carried at Close of Period
Land	51,093
Building & Improvements (3)	335,459
Total	386,552
Accumulated Depreciation	112,937
485 Lexington Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	450,000
Initial Cost
Land	78,282
Building & Improvements	452,631
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	(15,086)
Gross Amount at Which Carried at Close of Period
Land	78,282
Building & Improvements (3)	437,545
Total	515,827
Accumulated Depreciation	201,735
810 Seventh Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	114,077
Building & Improvements	550,819
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	5,406
Gross Amount at Which Carried at Close of Period
Land	114,077
Building & Improvements (3)	556,225
Total	670,302
Accumulated Depreciation	238,462
1185 Avenue of the Americas
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	0
Building & Improvements	791,106
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	139,416
Gross Amount at Which Carried at Close of Period
Land	0
Building & Improvements (3)	930,522
Total	930,522
Accumulated Depreciation	404,093
1350 Avenue of the Americas
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	90,941
Building & Improvements	431,517
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	14,566
Gross Amount at Which Carried at Close of Period
Land	90,941
Building & Improvements (3)	446,083
Total	537,024
Accumulated Depreciation	196,985
1-6 Landmark Square
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	100,000
Initial Cost
Land	27,852
Building & Improvements	161,343
Cost Capitalized Subsequent To Acquisition
Land	(6,939)
Building & Improvements	(23,245)
Gross Amount at Which Carried at Close of Period
Land	20,913
Building & Improvements (3)	138,098
Total	159,011
Accumulated Depreciation	46,789
7 Landmark Square
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	1,721
Building & Improvements	8,417
Cost Capitalized Subsequent To Acquisition
Land	(1,338)
Building & Improvements	(6,240)
Gross Amount at Which Carried at Close of Period
Land	383
Building & Improvements (3)	2,177
Total	2,560
Accumulated Depreciation	695
100 Church Street
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	370,000
Initial Cost
Land	34,994
Building & Improvements	183,932
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	11,060
Gross Amount at Which Carried at Close of Period
Land	34,994
Building & Improvements (3)	194,992
Total	229,986
Accumulated Depreciation	78,305
125 Park Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	120,900
Building & Improvements	270,598
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	23,312
Gross Amount at Which Carried at Close of Period
Land	120,900
Building & Improvements (3)	293,910
Total	414,810
Accumulated Depreciation	129,990
19 East 65th Street
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	8,603
Building & Improvements	2,074
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	3,345
Gross Amount at Which Carried at Close of Period
Land	8,603
Building & Improvements (3)	5,419
Total	14,022
Accumulated Depreciation	7
304 Park Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	54,489
Building & Improvements	90,643
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	9,096
Gross Amount at Which Carried at Close of Period
Land	54,489
Building & Improvements (3)	99,739
Total	154,228
Accumulated Depreciation	33,134
752-760 Madison Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	284,286
Building & Improvements	8,314
Cost Capitalized Subsequent To Acquisition
Land	(2,450)
Building & Improvements	187,847
Gross Amount at Which Carried at Close of Period
Land	281,836
Building & Improvements (3)	196,161
Total	477,997
Accumulated Depreciation	4,991
719 Seventh Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	50,000
Initial Cost
Land	41,180
Building & Improvements	46,232
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	(4,720)
Gross Amount at Which Carried at Close of Period
Land	41,180
Building & Improvements (3)	41,512
Total	82,692
Accumulated Depreciation	5,986
110 Greene Street
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	45,120
Building & Improvements	228,393
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	4,578
Gross Amount at Which Carried at Close of Period
Land	45,120
Building & Improvements (3)	232,971
Total	278,091
Accumulated Depreciation	57,067
185 Broadway
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	190,148
Initial Cost
Land	45,540
Building & Improvements	27,865
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	207,635
Gross Amount at Which Carried at Close of Period
Land	45,540
Building & Improvements (3)	235,500
Total	281,040
Accumulated Depreciation	12,200
690 Madison Avenue
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	60,000
Initial Cost
Land	13,820
Building & Improvements	51,732
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	28
Gross Amount at Which Carried at Close of Period
Land	13,820
Building & Improvements (3)	51,760
Total	65,580
Accumulated Depreciation	3,863
Other
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	0
Initial Cost
Land	20,635
Building & Improvements	16,224
Cost Capitalized Subsequent To Acquisition
Land	2,302
Building & Improvements	611,561
Gross Amount at Which Carried at Close of Period
Land	22,937
Building & Improvements (3)	627,785
Total	650,722
Accumulated Depreciation	$ 33,669
885 Third Avenue
Gross Amount at Which Carried at Close of Period
Approximate Square Feet | ft²		414,317
719 Seventh Avenue | 719 Seventh Avenue
Gross Amount at Which Carried at Close of Period
Interest in property (as a percent)	75.00%