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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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- Definition

ale Of Ownership Interest Percent in real estate property sold.

+ References

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Investments in Partially Owned Entities (Summary of Investments) (Details) - USD ($) $ in Thousands	May 27, 2016	Jun. 30, 2018	Dec. 31, 2017
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities		$ 959,801	$ 1,056,829
Other liabilities
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities		$ (105,826)	(101,368)
7 West 34th Street \| Other liabilities
Schedule Of Equity Method Investments
Equity method ownership percentage		53.00%
Carrying amount of investments in partially owned entities		$ (49,363)	(47,369)
Sale of ownership interest, percent	47.00%
330 Madison Avenue \| Other liabilities
Schedule Of Equity Method Investments
Equity method ownership percentage		25.00%
Carrying amount of investments in partially owned entities		$ (56,463)	(53,999)
Partially Owned Office Buildings
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities		$ 503,240	504,393
Alexanders Inc
Schedule Of Equity Method Investments
Equity method ownership percentage		32.40%
Carrying amount of investments in partially owned entities		$ 114,768	126,400
PREIT
Schedule Of Equity Method Investments
Equity method ownership percentage		8.00%
Carrying amount of investments in partially owned entities		$ 63,240	66,572
UE
Schedule Of Equity Method Investments
Equity method ownership percentage		4.50%
Carrying amount of investments in partially owned entities		$ 43,960	46,152
Other investments
Schedule Of Equity Method Investments
Carrying amount of investments in partially owned entities		$ 234,593	$ 313,312