Income (Loss) Per Share/Income (Loss) Per Class A Unit (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Numerator:
Income (loss) from continuing operations, net of (income) loss attributable to noncontrolling interests in consolidated subsidiaries	$ 65,700	$ 335,445	$ (102,026)	$ 2,942,267
Loss from discontinued operations	0	(7)	0	(80)
Net (loss) income attributable to Vornado / Vornado Realty L.P.	65,700	335,438	(102,026)	2,942,187
Preferred share dividends / unit distributions	(12,530)	(12,532)	(37,591)	(37,598)
NET (LOSS) INCOME attributable to common shareholders / Class A unitholders	53,170	322,906	(139,617)	2,904,589
Earnings allocated to unvested participating securities	(15)	(33)	(84)	(291)
Numerator for basic income (loss) per share / per Class A unit	53,155	322,873	(139,701)	2,904,298
Convertible preferred share dividends / unit distributions	0	14	0	43
Earnings Allocated To Out-Performance Plan units	0	0	0	9
Numerator for diluted (loss) income per share	$ 53,155	$ 322,887	$ (139,701)	$ 2,904,350
Denominator:
Denominator for basic income (loss) per share - weighted average shares (in shares)	191,162	190,814	191,102	190,762
Vornado Stock Options, Vornado Restricted Stock Awards, OP Units, AO LTIP Units and OPPs (in shares)	0	176	0	227
Convertible preferred shares/units (in shares)	0	34	0	35
Out-Performance Plan units (in shares)	0	0	0	3
Denominator for diluted income (loss) per share - weighted average shares and assumed conversions (in shares)	191,162	191,024	191,102	191,027
INCOME (LOSS) PER COMMON SHARE - BASIC:
Net income (loss) per common share (in dollars per share)	$ 0.28	$ 1.69	$ (0.73)	$ 15.22
INCOME (LOSS) PER COMMON SHARE - DILUTED:
Net income (loss) per common share (in dollars per share)	$ 0.28	$ 1.69	$ (0.73)	$ 15.20
Vornado Realty L.P.
Numerator:
Income (loss) from continuing operations, net of (income) loss attributable to noncontrolling interests in consolidated subsidiaries	$ 69,584	$ 358,083	$ (112,116)	$ 3,139,626
Loss from discontinued operations	0	(8)	0	(85)
Net (loss) income attributable to Vornado / Vornado Realty L.P.	69,584	358,075	(112,116)	3,139,541
Preferred share dividends / unit distributions	(12,572)	(12,574)	(37,715)	(37,722)
NET (LOSS) INCOME attributable to common shareholders / Class A unitholders	57,012	345,501	(149,831)	3,101,819
Earnings allocated to unvested participating securities	(734)	(2,449)	(4,685)	(14,807)
Numerator for basic income (loss) per share / per Class A unit	56,278	343,052	(154,516)	3,087,012
Convertible preferred share dividends / unit distributions	0	14	0	43
Numerator for diluted (loss) income per Class A unit	$ 56,278	$ 343,066	$ (154,516)	$ 3,087,055
Denominator:
Denominator for basic (loss) income per Class A unit – weighted average units (in shares)	203,554	203,009	203,480	202,903
Vornado Stock Options, Vornado Restricted Stock Awards, OP Units, AO LTIP Units and OPPs (in shares)	0	507	0	478
Convertible preferred shares/units (in shares)	0	34	0	35
Denominator for diluted income (loss) per Class A unit - weighted average units and assumed conversions (in shares)	203,554	203,550	203,480	203,416
INCOME (LOSS) PER CLASS A UNIT - BASIC:
Net income (loss) per Class A unit (in dollars per unit)	$ 0.28	$ 1.69	$ (0.76)	$ 15.21
INCOME (LOSS) PER CLASS A UNIT - DILUTED:
Net income (loss) per Class A unit (in dollars per unit)	$ 0.28	$ 1.69	$ (0.76)	$ 15.18