Income (Loss) Per Share/Income (Loss) Per Class A Unit (Narrative) (Details) - shares shares in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share
Weighted average common share / class A unit equivalents of excluded dilutive securities due to anti-dilutive effect	14,159	13,431	14,007	13,067
Vornado Realty L.P.
Antidilutive Securities Excluded From Computation Of Earnings Per Share
Weighted average common share / class A unit equivalents of excluded dilutive securities due to anti-dilutive effect	1,767	905	1,629	678

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration