Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Information [Line Items]
Total Revenues	$ 633,197	$ 627,596	$ 1,867,942	$ 1,850,686
Total expenses	444,044	436,156	1,492,255	1,298,141
Operating income	189,153	191,440	375,687	552,545
Income (loss) from partially owned entities	4,127	(325)	529	(8,709)
Income from real estate fund investments	1,077	1,665	28,750	52,122
Interest and other investment income, net	6,508	3,160	20,262	19,618
Interest and debt expense	(98,365)	(95,344)	(304,430)	(279,110)
Net gain on disposition of wholly owned and partially owned assets	0	103,037	160,225	104,897
Income (loss) before income taxes	102,500	203,633	281,023	441,363
Income tax (expense) benefit	(4,865)	(2,856)	(9,805)	84,245
Income (loss) from continuing operations	97,635	200,777	271,218	525,608
Income from discontinued operations	2,969	34,463	6,160	50,278
Net income	100,604	235,240	277,378	575,886
Net income attributable to Vornado	92,580	219,234	239,607	509,327
Net income attributable to noncontrolling interest in the Operating Partnership	4,366	12,704	11,410	28,189
Operating Segments
Segment Information [Line Items]
Total Revenues	633,197	627,596	1,867,942	1,850,686
Total expenses	444,044	436,156	1,492,255	1,298,141
Operating income	189,153	191,440	375,687	552,545
Income (loss) from partially owned entities	4,127	(325)	529	(8,709)
Income from real estate fund investments	1,077	1,665	28,750	52,122
Interest and other investment income, net	6,508	3,160	20,262	19,618
Interest and debt expense	(98,365)	(95,344)	(304,430)	(279,110)
Net gain on disposition of wholly owned and partially owned assets		103,037	160,225	104,897
Income (loss) before income taxes	102,500	203,633	281,023	441,363
Income tax (expense) benefit	(4,865)	(2,856)	(9,805)	84,245
Income (loss) from continuing operations	97,635	200,777	271,218	525,608
Income from discontinued operations	2,969	34,463	6,160	50,278
Net income	100,604	235,240	277,378	575,886
Less net income attributable to noncontrolling interests	(8,024)	(16,006)	(37,771)	(66,559)
Net income attributable to Vornado	92,580	219,234	239,607	509,327
Net income attributable to noncontrolling interest in the Operating Partnership	4,366	12,704	11,410	28,189
Interest and debt expense	122,979	118,977	376,898	348,725
Depreciation and amortization	172,980	174,209	521,143	493,904
Income tax (benefit) expense	5,102	3,043	13,067	(85,349)
EBITDA	398,007	528,167	1,162,125	1,294,796
New York Segment | Operating Segments
Segment Information [Line Items]
Total Revenues	432,869	429,433	1,269,464	1,243,208
Total expenses	280,689	263,805	818,419	766,863
Operating income	152,180	165,628	451,045	476,345
Income (loss) from partially owned entities	(579)	4,010	(5,143)	1,523
Income from real estate fund investments	0	0	0	0
Interest and other investment income, net	1,355	1,888	3,684	5,642
Interest and debt expense	(51,212)	(50,480)	(162,193)	(143,004)
Net gain on disposition of wholly owned and partially owned assets		0	159,511	0
Income (loss) before income taxes	101,744	121,046	446,904	340,506
Income tax (expense) benefit	(2,356)	(1,147)	(4,131)	(3,185)
Income (loss) from continuing operations	99,388	119,899	442,773	337,321
Income from discontinued operations	0	0	0	0
Net income	99,388	119,899	442,773	337,321
Less net income attributable to noncontrolling interests	(2,985)	(2,582)	(9,811)	(6,640)
Net income attributable to Vornado	96,403	117,317	432,962	330,681
Net income attributable to noncontrolling interest in the Operating Partnership	0	0	0	0
Interest and debt expense	66,314	64,653	208,683	184,377
Depreciation and amortization	111,731	99,206	331,448	288,897
Income tax (benefit) expense	2,445	1,214	4,424	3,368
EBITDA	276,893	282,390	977,517	807,323
Washington DC Segment | Operating Segments
Segment Information [Line Items]
Total Revenues	134,446	132,704	389,926	401,528
Total expenses	90,756	102,114	436,427	293,772
Operating income	43,690	30,590	(46,501)	107,756
Income (loss) from partially owned entities	(452)	(1,909)	(5,453)	(3,583)
Income from real estate fund investments	0	0	0	0
Interest and other investment income, net	49	34	141	60
Interest and debt expense	(18,644)	(16,580)	(54,396)	(52,223)
Net gain on disposition of wholly owned and partially owned assets		102,404	0	102,404
Income (loss) before income taxes	24,643	114,539	(106,209)	154,414
Income tax (expense) benefit	(302)	(287)	(884)	(79)
Income (loss) from continuing operations	24,341	114,252	(107,093)	154,335
Income from discontinued operations	0	0	0	0
Net income	24,341	114,252	(107,093)	154,335
Less net income attributable to noncontrolling interests	0	0	0	0
Net income attributable to Vornado	24,341	114,252	(107,093)	154,335
Net income attributable to noncontrolling interest in the Operating Partnership	0	0	0	0
Interest and debt expense	20,991	20,010	63,038	62,413
Depreciation and amortization	37,123	48,132	119,109	136,687
Income tax (benefit) expense	310	294	2,780	(1,856)
EBITDA	82,765	182,688	77,834	351,579
Other Segment | Operating Segments
Segment Information [Line Items]
Total Revenues	65,882	65,459	208,552	205,950
Total expenses	72,599	70,237	237,409	237,506
Operating income	(6,717)	(4,778)	(28,857)	(31,556)
Income (loss) from partially owned entities	5,158	(2,426)	11,125	(6,649)
Income from real estate fund investments	1,077	1,665	28,750	52,122
Interest and other investment income, net	5,104	1,238	16,437	13,916
Interest and debt expense	(28,509)	(28,284)	(87,841)	(83,883)
Net gain on disposition of wholly owned and partially owned assets		633	714	2,493
Income (loss) before income taxes	(23,887)	(31,952)	(59,672)	(53,557)
Income tax (expense) benefit	(2,207)	(1,422)	(4,790)	87,509
Income (loss) from continuing operations	(26,094)	(33,374)	(64,462)	33,952
Income from discontinued operations	2,969	34,463	6,160	50,278
Net income	(23,125)	1,089	(58,302)	84,230
Less net income attributable to noncontrolling interests	(5,039)	(13,424)	(27,960)	(59,919)
Net income attributable to Vornado	(28,164)	(12,335)	(86,262)	24,311
Net income attributable to noncontrolling interest in the Operating Partnership	4,366	12,704	11,410	28,189
Interest and debt expense	35,674	34,314	105,177	101,935
Depreciation and amortization	24,126	26,871	70,586	68,320
Income tax (benefit) expense	2,347	1,535	5,863	(86,861)
EBITDA	$ 38,349	$ 63,089	$ 106,774	$ 135,894