(Loss) Income Per Share/(Loss) Income Per Class A Unit (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator:
(Loss) income from continuing operations, net of income attributable to noncontrolling interests in consolidated subsidiaries	$ (185,220)	$ 2,412,671	$ (167,726)	$ 2,606,821
Income (loss) from discontinued operations	0	56	0	(72)
Net (loss) income attributable to Vornado / Vornado Realty L.P.	(185,220)	2,412,727	(167,726)	2,606,749
Preferred share dividends / unit distributions	(12,530)	(12,532)	(25,061)	(25,066)
NET (LOSS) INCOME attributable to common shareholders / Class A unitholders	(197,750)	2,400,195	(192,787)	2,581,683
Earnings allocated to unvested participating securities	(18)	(239)	(69)	(258)
Numerator for basic income (loss) per share / per Class A unit	(197,768)	2,399,956	(192,856)	2,581,425
Convertible preferred share dividends / unit distributions	0	14	0	29
Earnings allocated to Out-Performance Plan units	0	0	0	9
Numerator for diluted (loss) income per share	$ (197,768)	$ 2,399,970	$ (192,856)	$ 2,581,463
Denominator:
Denominator for basic (loss) income per share - weighted average shares (in shares)	191,104	190,781	191,071	190,735
Vornado employee stock options and restricted share / unit awards (in shares)	0	243	0	256
Convertible preferred shares/units	0	34	0	35
Out-Performance Plan units	0	0	0	4
Denominator for diluted (loss) income per share - weighted average shares and assumed conversions (in shares)	191,104	191,058	191,071	191,030
(LOSS) INCOME PER COMMON SHARE - BASIC:
Net (loss) income per common share (in dollars per share)	$ (1.03)	$ 12.58	$ (1.01)	$ 13.53
(LOSS) INCOME PER COMMON SHARE - DILUTED:
Net (loss) income per common share (in dollars per share)	$ (1.03)	$ 12.56	$ (1.01)	$ 13.51
Vornado Realty L.P.
Numerator:
(Loss) income from continuing operations, net of income attributable to noncontrolling interests in consolidated subsidiaries	$ (199,584)	$ 2,575,182	$ (181,700)	$ 2,781,543
Income (loss) from discontinued operations	0	60	0	(77)
Net (loss) income attributable to Vornado / Vornado Realty L.P.	(199,584)	2,575,242	(181,700)	2,781,466
Preferred share dividends / unit distributions	(12,571)	(12,573)	(25,143)	(25,148)
NET (LOSS) INCOME attributable to common shareholders / Class A unitholders	(212,155)	2,562,669	(206,843)	2,756,318
Earnings allocated to unvested participating securities	(1,439)	(10,162)	(6,357)	(10,860)
Numerator for basic income (loss) per share / per Class A unit	(213,594)	2,552,507	(213,200)	2,745,458
Convertible preferred share dividends / unit distributions	0	14	0	29
Numerator for diluted (loss) income per Class A unit	$ (213,594)	$ 2,552,521	$ (213,200)	$ 2,745,487
Denominator:
Denominator for basic (loss) income per Class A unit – weighted average units (in shares)	203,512	202,924	203,441	202,848
Vornado employee stock options and restricted share / unit awards (in shares)	0	522	0	508
Convertible preferred shares/units	0	34	0	35
Denominator for diluted (loss) income per Class A unit - weighted average units and assumed conversions	203,512	203,480	203,441	203,391
(LOSS) INCOME PER CLASS A UNIT - BASIC:
Net (loss) income per Class A unit (in dollars per unit)	$ (1.05)	$ 12.58	$ (1.05)	$ 13.53
(LOSS) INCOME PER CLASS A UNIT - DILUTED:
Net (loss) income per Class A unit (in dollars per unit)	$ (1.05)	$ 12.54	$ (1.05)	$ 13.50