Consolidated Statements of Changes in Equity - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Redeemable Preferred Unit	Series J	JBGS	Real estate fund investments	Other	Preferred Shares / Units	Preferred Shares / Units Cumulative Redeemable Preferred Unit	Preferred Shares / Units Series J	Common Shares	Additional Capital	Earnings Less Than Distributions	Earnings Less Than Distributions Series J	Earnings Less Than Distributions JBGS	Accumulated Other Comprehensive Income (Loss)	Non- controlling Interests in Consolidated Subsidiaries	Non- controlling Interests in Consolidated Subsidiaries Real estate fund investments	Non- controlling Interests in Consolidated Subsidiaries Other	Vornado Realty L.P.	Vornado Realty L.P. Cumulative Redeemable Preferred Unit	Vornado Realty L.P. Series J	Vornado Realty L.P. JBGS	Vornado Realty L.P. Real estate fund investments	Vornado Realty L.P. Other	Vornado Realty L.P. Preferred Shares / Units	Vornado Realty L.P. Preferred Shares / Units Cumulative Redeemable Preferred Unit	Vornado Realty L.P. Preferred Shares / Units Series J	Vornado Realty L.P. Class A Units Owned by Vornado	Vornado Realty L.P. Additional Capital Series J	Vornado Realty L.P. Earnings Less Than Distributions	Vornado Realty L.P. Earnings Less Than Distributions JBGS	Vornado Realty L.P. Accumulated Other Comprehensive Income (Loss)	Vornado Realty L.P. Non- controlling Interests in Consolidated Subsidiaries	Vornado Realty L.P. Non- controlling Interests in Consolidated Subsidiaries Real estate fund investments	Vornado Realty L.P. Non- controlling Interests in Consolidated Subsidiaries Other
Beginning balance, Shares at Dec. 31, 2015							52,677			188,577															52,677			188,577
Beginning balance, Value at Dec. 31, 2015	$ 7,476,078						$ 1,276,954			$ 7,521	$ 7,132,979	$ (1,766,780)			$ 46,921	$ 778,483			$ 7,476,078						$ 1,276,954			$ 7,140,500		$ (1,766,780)		$ 46,921	$ 778,483
Net income attributable to Vornado / Vornado Realty L.P.	906,917											906,917							960,571											960,571
Net income attributable to redeemable partnership units	(53,654)																		(53,654)											(53,654)
Net (loss) income attributable to noncontrolling interests in consolidated subsidiaries	21,351				$ (2,560)											21,351			21,351														21,351
Dividends on common shares	(475,961)											(475,961)
Distributions to Vornado																			(475,961)											(475,961)
Dividends on preferred shares / Distributions to preferred unitholders	(75,903)											(75,903)							(75,903)											(75,903)
Redemption of preferred shares, Shares / Units									(9,850)																		(9,850)
Redemption of preferred shares, Value			$ (246,250)						$ (238,842)				$ (7,408)								$ (246,250)						$ (238,842)		$ (7,408)
Common shares issued:
Upon redemption of Class A units, at redemption value, Shares										376																		376
Upon redemption of Class A units, at redemption value, Value	36,510									$ 15	36,495								36,510									$ 36,510
Under Vornado's employees' share option plan, Shares										123																		123
Under Vornado's employees' share option plan, Value	6,825									$ 5	6,820								6,825									$ 6,825		0
Under dividend reinvestment plan, Shares										16																		16
Under dividend reinvestment plan, Value	1,444									$ 1	1,443								1,444									$ 1,444
Contributions
Contributions	19,749															19,749			19,749														19,749
Distributions:
Distributions					(62,444)	$ (36,804)											$ (62,444)	$ (36,804)					$ (62,444)	$ (36,804)										$ (62,444)	$ (36,804)
Conversion of Series A preferred shares to common shares / Conversion of Series A preferred units to Class A units							(2)			3															(2)			3
Conversion of Series A preferred shares to common shares / Conversion of Series A preferred units to Class A units, Value	0						$ (56)			$ 0	56														$ (56)			$ 56
Deferred compensation shares / units and options, Shares										7																		7
Deferred compensation shares / units and options, Value	1,602									$ 0	1,788	(186)							1,602									$ 1,788		(186)
(Reduction) increase in unrealized net gain on available-for-sale securities	52,057														52,057				52,057													52,057
Pro rata share of other comprehensive income (loss) of nonconsolidated subsidiaries	(2,739)														(2,739)				(2,739)													(2,739)
Increase/(reduction) in value of interest rate swaps	27,434														27,434				27,434													27,434
Adjustments to carry redeemable Class A units at redemption value	(26,251)										(26,251)								(26,251)									$ (26,251)
Redeemable noncontrolling interests' share of above adjustments	(4,699)														(4,699)				(4,699)													(4,699)
Other, Shares										(1)															0			(1)
Other	(420)						$ (1)			$ 0	2	(61)			(2)	(358)			(420)						$ (1)			$ 2		(61)		(2)	(358)
Ending balance, Shares at Dec. 31, 2016							42,825			189,101															42,825			189,101
Ending balance, Value at Dec. 31, 2016	7,618,496						$ 1,038,055			$ 7,542	7,153,332	(1,419,382)			118,972	719,977			7,618,496						$ 1,038,055			$ 7,160,874		(1,419,382)		118,972	719,977
Net income attributable to Vornado / Vornado Realty L.P.	227,416											227,416							238,326											238,326
Net income attributable to redeemable partnership units	(10,910)																		(10,910)											(10,910)
Net (loss) income attributable to noncontrolling interests in consolidated subsidiaries	25,802				14,044											25,802			25,802														25,802
Dividends on common shares	(496,490)											(496,490)
Distributions to Vornado																			(496,490)											(496,490)
Dividends on preferred shares / Distributions to preferred unitholders	(65,399)											(65,399)							(65,399)											(65,399)
Common shares issued:
Upon redemption of Class A units, at redemption value, Shares										403																		403
Upon redemption of Class A units, at redemption value, Value	38,747									$ 16	38,731								38,747									$ 38,747
Under Vornado's employees' share option plan, Shares										449																		449
Under Vornado's employees' share option plan, Value	28,253									$ 18	28,235	0							28,253									$ 28,253
Under dividend reinvestment plan, Shares										17																		17
Under dividend reinvestment plan, Value	1,459									$ 1	1,458								1,459									$ 1,459
Contributions
Contributions	1,044															1,044			1,044														1,044
Distributions:
Distributions	(33,229)			$ (2,428,345)	(73,850)	(2,618)								$ (2,428,345)			(73,850)	(2,618)				$ (2,428,345)	(73,850)	(2,618)							$ (2,428,345)			(73,850)	(2,618)
Conversion of Series A preferred shares to common shares / Conversion of Series A preferred units to Class A units							(5)			10															(5)			10
Conversion of Series A preferred shares to common shares / Conversion of Series A preferred units to Class A units, Value	0						$ (162)			$ 0	162								0						$ (162)			$ 162
Deferred compensation shares / units and options, Shares										0																		0
Deferred compensation shares / units and options, Value	1,828									$ 0	2,246	(418)							1,828									$ 2,246		(418)
(Reduction) increase in unrealized net gain on available-for-sale securities	(20,951)														(20,951)				(20,951)													(20,951)
Pro rata share of amounts reclassified related to a nonconsolidated subsidiary	14,402														14,402				14,402													14,402
Pro rata share of other comprehensive income (loss) of nonconsolidated subsidiaries	1,425														1,425				1,425													1,425
Increase/(reduction) in value of interest rate swaps	15,476														15,476				15,476													15,476
Adjustments to carry redeemable Class A units at redemption value	268,494										268,494								268,494									$ 268,494
Preferred shares issuance, Shares							12,780																		12,780
Preferred shares issuance, Value	309,609						$ 309,609												309,609						$ 309,609
Cumulative redeemable preferred shares called for redemption, units								(18,800)																		(18,800)
Cumulative redeemable preferred shares called for redemption		$ (455,514)						$ (455,514)												$ (455,514)						$ (455,514)
Redeemable noncontrolling interests' share of above adjustments	(642)														(642)				(642)													(642)
Other, Shares							0			4																		4
Other	(941)						$ 0				0	(635)			0	(306)			(941)											(635)			(306)
Ending balance, Shares at Dec. 31, 2017							36,800			189,984															36,800			189,984
Ending balance, Value at Dec. 31, 2017	5,007,701						$ 891,988			$ 7,577	7,492,658	(4,183,253)			128,682	670,049			5,007,701						$ 891,988			$ 7,500,235		(4,183,253)		128,682	670,049
Cumulative effect of accounting change (see Note 2)																			14,519											122,893		(108,374)
Net income attributable to Vornado / Vornado Realty L.P.	449,954											449,954							475,626											475,626
Net income attributable to redeemable partnership units	(25,672)																		(25,672)											(25,672)
Net (loss) income attributable to noncontrolling interests in consolidated subsidiaries	(53,023)				(61,230)											(53,023)			(53,023)														(53,023)
Dividends on common shares	(479,348)											(479,348)
Distributions to Vornado																			(479,348)											(479,348)
Dividends on preferred shares / Distributions to preferred unitholders	(50,636)											(50,636)							(50,636)											(50,636)
Common shares issued:
Upon redemption of Class A units, at redemption value, Shares										244																		244
Upon redemption of Class A units, at redemption value, Value	17,068									$ 10	17,058								17,068									$ 17,068
Under Vornado's employees' share option plan, Shares										279																		279
Under Vornado's employees' share option plan, Value	(6,266)									$ 12	5,907	(12,185)							(6,266)									$ 5,919		(12,185)
Under dividend reinvestment plan, Shares										20																		20
Under dividend reinvestment plan, Value	1,390									$ 1	1,389								1,390									$ 1,390
Contributions
Contributions	62,657															62,657			62,657														62,657
Distributions:
Distributions	(31,828)				$ (12,665)	$ (33,250)											$ (12,665)	$ (33,250)					$ (12,665)	$ (33,250)										$ (12,665)	$ (33,250)
Conversion of Series A preferred shares to common shares / Conversion of Series A preferred units to Class A units							0			2															0			2
Conversion of Series A preferred shares to common shares / Conversion of Series A preferred units to Class A units, Value	(1)						$ (31)			$ 0	30								(1)						$ (31)			$ 30
Deferred compensation shares / units and options, Shares										6																		6
Deferred compensation shares / units and options, Value	1,036									$ 0	1,157	(121)							1,036									$ 1,157		(121)
(Reduction) increase in unrealized net gain on available-for-sale securities	0																		0
Pro rata share of other comprehensive income (loss) of nonconsolidated subsidiaries	1,155														1,155				1,155													1,155
Increase/(reduction) in value of interest rate swaps	(14,634)														(14,634)				(14,634)													(14,634)
Unearned 2015 Out-Performance Plan awards acceleration	9,046										9,046								9,046									9,046
Adjustments to carry redeemable Class A units at redemption value	198,064										198,064								198,064									198,064
Preferred shares issuance, Shares							0
Preferred shares issuance, Value	(15,149)						$ (663)					(14,486)							(15,149)						$ (663)					(14,486)
Redeemable noncontrolling interests' share of above adjustments	836														836				836													836
Consolidation of the Farley joint venture	8,720															8,720			8,720														8,720
Other	709										548	(2)			(1)	164			709									$ 548		(2)		(1)	164
Ending balance, Shares at Dec. 31, 2018							36,800			190,535															36,800			190,535
Ending balance, Value at Dec. 31, 2018	5,107,883						$ 891,294			$ 7,600	$ 7,725,857	(4,167,184)			7,664	$ 642,652			$ 5,107,883						$ 891,294			$ 7,733,457		$ (4,167,184)		$ 7,664	$ 642,652
Cumulative effect of accounting change (see Note 2)	$ 14,519											$ 122,893			$ (108,374)