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The percentage of economic interest in the investee accounted for under the equity method of accounting.

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Equity Method Investments, Ownership Percentage Acquired

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Equity Method Investments, Ownership Percentage, Increase (Decrease)

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Equity Method Investments With Negative Book Value

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Investment In Joint Venture Aggregate Equity Committed By Partner

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Investment In Joint Venture Aggregate Maximum Ownership Percentage

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Investment in Joint Venture, Number Of Partners In Joint Venture

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Investment in Joint Venture, Partners' Ownership Percentage

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Number Of Residential Units

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Represents the amount of equity investment in variable interest entities (VIEs) in which the entity is not a primary beneficiary.

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Area of a real estate property.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Represents the number of stores.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Investments in Unconsolidated Joint Ventures - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2021	Dec. 31, 2021 USD ($) ft² partner unit	Dec. 31, 2021 USD ($) ft² partner unit	Dec. 31, 2020 USD ($)	Nov. 30, 2021 USD ($)	Jul. 31, 2021 USD ($) ft²
General information on each joint venture
Investments in unconsolidated joint ventures \| $		$ 2,997,934	$ 2,997,934	$ 3,823,322
Net equity investment in VIEs in which the entity is not primary beneficiary \| $		$ 85,600	$ 85,600	134,000
Approximate Square Feet		27,716,872	27,716,872
21 East 66th Street \| Three Retail and Two Residential Units
General information on each joint venture
Ownership interest		32.28%	32.28%
Number of stores \| unit		3	3
Number of residential units \| unit		1	1
21 East 66th Street \| Three Residential Units
General information on each joint venture
Ownership interest		16.14%	16.14%
Number of residential units \| unit		2	2
Stonehenge Portfolio
General information on each joint venture
Asset impairment loss \| $		$ 3,100
Gross asset valuation \| $		$ 1,000	$ 1,000
Worldwide Plaza
General information on each joint venture
Ownership percentage acquired	1.20%
Increase in ownership interest	0.60%
One Madison Avenue
General information on each joint venture
Investment in joint venture aggregate equity committed by partner \| $				$ 492,200	$ 259,300
Investment in joint venture aggregate maximum ownership percentage				49.50%	25.00%
Investment in joint venture, number of partners \| partner		2	2
Investment in joint venture, ownership percentage		27.10%	27.10%
Joint venture
General information on each joint venture
Investments in unconsolidated joint ventures \| $		$ 2,997,934	$ 2,997,934
Equity method investments with negative book value \| $		$ 103,700	$ 103,700
Joint venture \| 100 Park Avenue
General information on each joint venture
Ownership interest		49.90%	49.90%
Economic Interest, percent		49.90%	49.90%
Approximate Square Feet		834,000	834,000
Joint venture \| 717 Fifth Avenue
General information on each joint venture
Ownership interest		10.92%	10.92%
Economic Interest, percent		10.92%	10.92%
Approximate Square Feet		119,500	119,500
Joint venture \| 800 Third Avenue
General information on each joint venture
Ownership interest		60.52%	60.52%
Economic Interest, percent		60.52%	60.52%
Approximate Square Feet		526,000	526,000
Joint venture \| 919 Third Avenue
General information on each joint venture
Ownership interest		51.00%	51.00%
Economic Interest, percent		51.00%	51.00%
Approximate Square Feet		1,454,000	1,454,000
Joint venture \| 11 West 34th Street
General information on each joint venture
Ownership interest		30.00%	30.00%
Economic Interest, percent		30.00%	30.00%
Approximate Square Feet		17,150	17,150
Joint venture \| 280 Park Avenue
General information on each joint venture
Ownership interest		50.00%	50.00%
Economic Interest, percent		50.00%	50.00%
Approximate Square Feet		1,219,158	1,219,158
Joint venture \| 1552-1560 Broadway
General information on each joint venture
Ownership interest		50.00%	50.00%
Economic Interest, percent		50.00%	50.00%
Approximate Square Feet		57,718	57,718
Joint venture \| 10 East 53rd Street
General information on each joint venture
Ownership interest		55.00%	55.00%
Economic Interest, percent		55.00%	55.00%
Approximate Square Feet		354,300	354,300
Joint venture \| 21 East 66th Street
General information on each joint venture
Ownership interest		32.28%	32.28%
Economic Interest, percent		32.28%	32.28%
Approximate Square Feet		13,069	13,069
Joint venture \| 650 Fifth Avenue
General information on each joint venture
Ownership interest		50.00%	50.00%
Economic Interest, percent		50.00%	50.00%
Approximate Square Feet		69,214	69,214
Joint venture \| 121 Greene Street
General information on each joint venture
Ownership interest		50.00%	50.00%
Economic Interest, percent		50.00%	50.00%
Approximate Square Feet		7,131	7,131
Joint venture \| Stonehenge Portfolio
General information on each joint venture
Approximate Square Feet		1,439,016	1,439,016
Joint venture \| 11 Madison Avenue
General information on each joint venture
Ownership interest		60.00%	60.00%
Economic Interest, percent		60.00%	60.00%
Approximate Square Feet		2,314,000	2,314,000
Joint venture \| One Vanderbilt Avenue
General information on each joint venture
Ownership interest		71.01%	71.01%
Economic Interest, percent		71.01%	71.01%
Approximate Square Feet		1,657,198	1,657,198
Joint venture \| Worldwide Plaza
General information on each joint venture
Ownership interest		24.95%	24.95%
Economic Interest, percent		24.95%	24.95%
Approximate Square Feet		2,048,725	2,048,725
Joint venture \| 1515 Broadway
General information on each joint venture
Ownership interest		56.87%	56.87%
Economic Interest, percent		56.87%	56.87%
Approximate Square Feet		1,750,000	1,750,000
Joint venture \| 2 Herald Square
General information on each joint venture
Ownership interest		51.00%	51.00%
Economic Interest, percent		51.00%	51.00%
Approximate Square Feet		369,000	369,000
Joint venture \| 115 Spring Street
General information on each joint venture
Ownership interest		51.00%	51.00%
Economic Interest, percent		51.00%	51.00%
Approximate Square Feet		5,218	5,218
Joint venture \| 15 Beekman
General information on each joint venture
Ownership interest		20.00%	20.00%
Economic Interest, percent		20.00%	20.00%
Approximate Square Feet		221,884	221,884
Joint venture \| 85 Fifth Avenue
General information on each joint venture
Ownership interest		36.27%	36.27%
Economic Interest, percent		36.27%	36.27%
Approximate Square Feet		12,946	12,946
Joint venture \| One Madison Avenue
General information on each joint venture
Ownership interest		25.50%	25.50%
Economic Interest, percent		25.50%	25.50%
Approximate Square Feet		1,048,700	1,048,700
Joint venture \| 220 East 42nd Street
General information on each joint venture
Ownership interest		51.00%	51.00%
Economic Interest, percent		51.00%	51.00%
Approximate Square Feet		1,135,000	1,135,000
One Madison Avenue
General information on each joint venture
Ownership percentage deconsolidated				50.50%
Investment fair value adjustment \| $				$ 187,500
220 East 42nd Street \| 220 East 42nd Street
General information on each joint venture
Ownership percentage deconsolidated						51.00%
Investment fair value adjustment \| $			$ 206,800
220 East 42nd Street
General information on each joint venture
Approximate Square Feet						1,135,000
Gross asset valuation \| $						$ 783,500
Ownership interest disposed						49.00%