(Loss) Income Per Share / (Loss) Income Per Class A Unit (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Numerator:
Income from continuing operations, net of income attributable to noncontrolling interests	$ 10,021	$ 49,519
(Loss) income from discontinued operations, net of income attributable to noncontrolling interests	(341)	14,362
Net income attributable to Vornado / Vornado Realty L.P.	9,680	63,881
Preferred share dividends / unit distributions	(13,035)	(16,129)
Preferred share / unit issuance costs	(14,486)	0
NET (LOSS) INCOME attributable to common shareholders & Class A unitholders	(17,841)	47,752
Earnings allocated to unvested participating securities	(11)	(15)
Numerator for basic (loss) income per share / per Class A unit	$ (17,852)	$ 47,737
Denominator:
Denominator for basic income (loss) per share - weighted average shares (in shares)	190,081	189,210
Vornado employee stock options and restricted share / unit awards (in shares)	0	1,162
Denominator for diluted (loss) income per share - weighted average shares and assumed conversions (in shares)	190,081	190,372
(LOSS) INCOME PER COMMON SHARE – BASIC:
(Loss) income from continuing operations, net (in dollars per share)	$ (0.09)	$ 0.18
Income from discontinued operations, net (in dollars per share)	0.00	0.07
Net (loss) income per common share (in dollars per share)	(0.09)	0.25
(LOSS) INCOME PER COMMON SHARE – DILUTED:
(Loss) income from continuing operations, net (in dollars per share)	(0.09)	0.18
Income from discontinued operations, net (in dollars per share)	0.00	0.07
Net (loss) income per common share (in dollars per share)	$ (0.09)	$ 0.25
Vornado Realty L.P.
Numerator:
Income from continuing operations, net of income attributable to noncontrolling interests	$ 8,919	$ 51,792
(Loss) income from discontinued operations, net of income attributable to noncontrolling interests	(363)	15,318
Net income attributable to Vornado / Vornado Realty L.P.	8,556	67,110
Preferred share dividends / unit distributions	(13,084)	(16,178)
Preferred share / unit issuance costs	(14,486)	0
NET (LOSS) INCOME attributable to common shareholders & Class A unitholders	(19,014)	50,932
Earnings allocated to unvested participating securities	(771)	(1,018)
Numerator for basic and diluted (loss) income per Class A unit	$ (19,785)	$ 49,914
Denominator:
Denominator for basic (loss) income per Class A unit – weighted average units	201,929	200,845
Vornado employee stock options and restricted share / unit awards (in shares)	0	1,802
Denominator for diluted (loss) income per Class A unit - weighted average units and assumed conversions	201,929	202,647
(LOSS) INCOME PER CLASS A UNIT – BASIC:
(Loss) income from continuing operations, net (in dollars per unit)	$ (0.10)	$ 0.17
Income from discontinued operations, net (in dollars per unit)	0.00	0.08
Net (loss) income per Class A unit (in dollars per unit)	(0.10)	0.25
(LOSS) INCOME PER CLASS A UNIT – DILUTED:
(Loss) income from continuing operations, net (in dollars per unit)	(0.10)	0.17
Income from discontinued operations, net (in dollars per unit)	0.00	0.08
Net (loss) income per Class A unit (in dollars per unit)	$ (0.10)	$ 0.25