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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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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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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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The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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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		6 Months Ended		12 Months Ended
	May 31, 2021	Apr. 30, 2021 USD ($)	Oct. 31, 2016	Jun. 30, 2021 USD ($) ft² unit partner	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) ft² unit partner	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
General information on each joint venture
Equity method investments \| $				$ 3,209,151		$ 3,209,151		$ 3,823,322
Net equity investment in VIEs in which the entity is not primary beneficiary \| $				$ 87,700		$ 87,700		$ 134,000
Unaudited Approximate Square Feet (sqft)				27,962,796		27,962,796
Gain on sale of real estate, net \| $				$ 98,960	$ 64,884	$ 97,572	$ 137,520
One Madison Avenue
General information on each joint venture
Ownership percentage deconsolidated								50.50%
Investment fair value adjustment \| $						$ 2,700		$ 187,500
Stonehenge Portfolio
General information on each joint venture
Ownership interest			90.00%
East 400 Street 57
General information on each joint venture
Ownership interest			51.00%
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
Investment in joint venture aggregate maximum ownership percentage								49.50%
Investment in joint venture, number of partners \| partner				2		2
Investment in joint venture, ownership percentage				9.00%		9.00%
East 400 Street 57
General information on each joint venture
Ownership percentage in disposed asset			49.00%
Asset impairment charges \| $		$ 5,700
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				3		3
Joint venture
General information on each joint venture
Equity method investments \| $				$ 3,209,151		$ 3,209,151
Equity method investments with negative book value \| $				$ 96,000		$ 96,000
Joint venture \| 100 Park Avenue
General information on each joint venture
Ownership interest				49.90%		49.90%
Economic Interest (as a percent)				49.90%		49.90%
Unaudited Approximate Square Feet (sqft)				834,000		834,000
Joint venture \| 717 Fifth Avenue
General information on each joint venture
Ownership interest				10.92%		10.92%
Economic Interest (as a percent)				10.92%		10.92%
Unaudited Approximate Square Feet (sqft)				119,500		119,500
Joint venture \| 800 Third Avenue
General information on each joint venture
Ownership interest				60.52%		60.52%
Economic Interest (as a percent)				60.52%		60.52%
Unaudited Approximate Square Feet (sqft)				526,000		526,000
Interest rate, fixed rate debt (as a percent)				3.37%		3.37%
Joint venture \| 919 Third Avenue
General information on each joint venture
Ownership interest				51.00%		51.00%
Economic Interest (as a percent)				51.00%		51.00%
Unaudited Approximate Square Feet (sqft)				1,454,000		1,454,000
Interest rate, fixed rate debt (as a percent)				5.12%		5.12%
Joint venture \| 11 West 34th Street
General information on each joint venture
Ownership interest				30.00%		30.00%
Economic Interest (as a percent)				30.00%		30.00%
Unaudited Approximate Square Feet (sqft)				17,150		17,150
Joint venture \| 280 Park Avenue
General information on each joint venture
Ownership interest				50.00%		50.00%
Economic Interest (as a percent)				50.00%		50.00%
Unaudited Approximate Square Feet (sqft)				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 (as a percent)				50.00%		50.00%
Unaudited Approximate Square Feet (sqft)				57,718		57,718
Joint venture \| 10 East 53rd Street
General information on each joint venture
Ownership interest				55.00%		55.00%
Economic Interest (as a percent)				55.00%		55.00%
Unaudited Approximate Square Feet (sqft)				354,300		354,300
Joint venture \| 21 East 66th Street
General information on each joint venture
Ownership interest				32.28%		32.28%
Economic Interest (as a percent)				32.28%		32.28%
Unaudited Approximate Square Feet (sqft)				13,069		13,069
Interest rate, fixed rate debt (as a percent)				3.60%		3.60%
Joint venture \| 650 Fifth Avenue
General information on each joint venture
Ownership interest				50.00%		50.00%
Economic Interest (as a percent)				50.00%		50.00%
Unaudited Approximate Square Feet (sqft)				69,214		69,214
Joint venture \| 121 Greene Street
General information on each joint venture
Ownership interest				50.00%		50.00%
Economic Interest (as a percent)				50.00%		50.00%
Unaudited Approximate Square Feet (sqft)				7,131		7,131
Joint venture \| Stonehenge Portfolio
General information on each joint venture
Ownership interest			10.00%
Unaudited Approximate Square Feet (sqft)				1,439,016		1,439,016
Interest rate, fixed rate debt (as a percent)				3.50%		3.50%
Joint venture \| 11 Madison Avenue
General information on each joint venture
Ownership interest				60.00%		60.00%
Economic Interest (as a percent)				60.00%		60.00%
Unaudited Approximate Square Feet (sqft)				2,314,000		2,314,000
Interest rate, fixed rate debt (as a percent)				3.84%		3.84%
Joint venture \| East 400 Street 57
General information on each joint venture
Ownership interest				51.00%		51.00%
Economic Interest (as a percent)				41.00%		41.00%
Unaudited Approximate Square Feet (sqft)				290,482		290,482
Interest rate, fixed rate debt (as a percent)				3.00%		3.00%
Joint venture \| One Vanderbilt
General information on each joint venture
Ownership interest				71.01%		71.01%
Economic Interest (as a percent)				71.01%		71.01%
Unaudited Approximate Square Feet (sqft)				1,657,198		1,657,198
Interest rate, fixed rate debt (as a percent)				2.95%		2.95%
Joint venture \| Worldwide Plaza
General information on each joint venture
Ownership interest				24.95%		24.95%
Economic Interest (as a percent)				24.95%		24.95%
Unaudited Approximate Square Feet (sqft)				2,048,725		2,048,725
Interest rate, fixed rate debt (as a percent)				3.98%		3.98%
Joint venture \| 1515 Broadway
General information on each joint venture
Ownership interest				56.87%		56.87%
Economic Interest (as a percent)				56.87%		56.87%
Unaudited Approximate Square Feet (sqft)				1,750,000		1,750,000
Interest rate, fixed rate debt (as a percent)				3.93%		3.93%
Joint venture \| 2 Herald Square
General information on each joint venture
Ownership interest				51.00%		51.00%
Economic Interest (as a percent)				51.00%		51.00%
Unaudited Approximate Square Feet (sqft)				369,000		369,000
Joint venture \| 115 Spring Street
General information on each joint venture
Ownership interest				51.00%		51.00%
Economic Interest (as a percent)				51.00%		51.00%
Unaudited Approximate Square Feet (sqft)				5,218		5,218
Joint venture \| 15 Beekman
General information on each joint venture
Ownership interest				20.00%		20.00%
Economic Interest (as a percent)				20.00%		20.00%
Unaudited Approximate Square Feet (sqft)				221,884		221,884
Joint venture \| 85 Fifth Avenue
General information on each joint venture
Ownership interest				36.30%		36.30%
Economic Interest (as a percent)				36.30%		36.30%
Unaudited Approximate Square Feet (sqft)				12,946		12,946
Joint venture \| One Madison Avenue
General information on each joint venture
Ownership interest				50.50%		50.50%
Economic Interest (as a percent)				50.50%		50.50%
Unaudited Approximate Square Feet (sqft)				1,048,700		1,048,700