Real Estate Fund Investments (Narrative) (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019 USD ($) investment	Dec. 31, 2018 USD ($) investment
Investment Holdings
Aggregate fair value of Real Estate Fund investments (in US Dollars)	$ 306,596	$ 318,758
Vornado Capital Partners Real Estate Fund
Investment Holdings
Equity method ownership percentage	25.00%
Investment fund period expiration date	2013-07
Term of the Fund, years	8 years
Investment period for commitments of the Fund, years	3 years
Real estate fund investments
Investment Holdings
Number of investments held by fund (investment) \| investment	4	4
Aggregate fair value of Real Estate Fund investments (in US Dollars)	$ 306,596	$ 318,758
Fair value below cost	22,968
Unfunded commitments of fund	44,194
Vornado Realty Trust
Investment Holdings
Unfunded commitments of fund	$ 13,969
Joint Venture \| Crowne Plaza Times Square Hotel Joint Venture
Investment Holdings
Equity method ownership percentage	57.10%
Crowne Plaza Time Square Hotel \| Joint Venture \| Crowne Plaza Times Square Hotel Joint Venture
Investment Holdings
Ownership percentage by noncontrolling owners	24.70%

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

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.

+ References

No definition available.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

Equity Commitment Fund Term, in years

+ References

No definition available.

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- Definition

Expiration date of the fund investment in YYYY-MM format.

+ References

No definition available.

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- Definition

The amount of excess fair value of investments over it's cost.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Investment Period Fund

+ References

No definition available.

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- Definition

Number Of Investments Held By Fund during the year.

+ References

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- Definition

This element represents the real estate assets related to the fund

+ References

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- Definition

Unfunded Commitments Of the Fund

+ References

No definition available.

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