Consolidated Statements of Changes in Equity (USD $) In Thousands, unless otherwise specified	Total	Real Estate Funds [Member]	All Other Except Real Estate Fund [Member]	Preferred Units [Member]	Class A Units Owned By Vornado [Member]	Earnings Less Than Distributions	Accumulated Other Comprehensive Income (Loss)	Non-controlling Interests	Non-controlling Interests Real Estate Funds [Member]	Non-controlling Interests All Other Except Real Estate Fund [Member]
Beginning balance, Value at Dec. 31, 2011	$ 7,508,447			$ 1,021,660	$ 7,134,631	$ (1,401,704)	$ 73,729	$ 680,131
Beginning balance, Units at Dec. 31, 2011				42,187	185,080
Net income	280,264					270,667		9,597
Net income attributable to redeemable partnership units	(19,145)					(19,145)
Distributions to Vornado	(127,973)					(127,973)
Distributions to preferred unitholders	(17,787)					(17,787)
Class A units issued to Vornado:
Upon redemption of redeemable Class A units, at redemption value, Units					158
Upon redemption of redeemable Class A units, at redemption value, Value	13,028				13,028
Under Vornado's Omnibus Share plan, Units					389
Under Vornado's Omnibus Share plan, Value	(8,811)				7,578	(16,389)
Under Vornado's dividend reinvestment plan, Units					5
Under Vornado's dividend reinvestment plan, Value	411				411
Distributions:
Distributions:		(21,856)							(21,856)
Conversion of Series A preferred units to Class A units, Units				(2)	3
Conversion of Series A preferred units to Class A units, Value	0			(105)	105
Deferred compensation units and options, Units					7
Deferred compensation units and options, Value	5,577				5,916	(339)
Change in unrealized net gain on securities available-for-sale	12,693						12,693
Pro rata share of other comprehensive loss of nonconsolidated subsidiaries	(21,944)						(21,944)
Change in value of interest rate swap	2,386						2,386
Adjustments to carry redeemable Class A units at redemption value	(96,061)				(96,061)
Redeemable partnership units' share of above adjustments	433						433
Preferred unit redemptions	0
Other	(125)						(123)	(2)
Ending balance, Value at Mar. 31, 2012	7,509,537			1,021,555	7,065,608	(1,312,670)	67,174	667,870
Ending balance, Units at Mar. 31, 2012				42,185	185,642
Beginning balance, Value at Dec. 31, 2012	7,904,144			1,240,278	7,202,878	(1,573,275)	(18,946)	1,053,209
Beginning balance, Units at Dec. 31, 2012				51,185	186,735
Net income	288,927					277,641		11,286
Net income attributable to redeemable partnership units	(14,719)					(14,719)
Distributions to Vornado	(136,342)					(136,342)
Distributions to preferred unitholders	(21,702)					(21,702)
Issuance of Series L preferred units, Units				12,000
Issuance of Series L preferred units, Value	290,710			290,710
Redemption of Series F and Series H preferred units, Units				(10,500)
Redemption of Series F and Series H preferred units, Value	(253,269)			(253,269)
Class A units issued to Vornado:
Upon redemption of redeemable Class A units, at redemption value, Units					162
Upon redemption of redeemable Class A units, at redemption value, Value	13,404				13,404
Under Vornado's Omnibus Share plan, Units					27
Under Vornado's Omnibus Share plan, Value	1,176				1,176
Under Vornado's dividend reinvestment plan, Units					5
Under Vornado's dividend reinvestment plan, Value	433				433
Contributions:
Contributions		10,251	14,316						10,251	14,316
Distributions:
Distributions:		(43,145)	(120,051)						(43,145)	(120,051)
Deferred compensation units and options, Units					6
Deferred compensation units and options, Value	2,208				2,513	(305)
Change in unrealized net gain on securities available-for-sale	148,789						148,789
Pro rata share of other comprehensive loss of nonconsolidated subsidiaries	(3,647)						(3,647)
Change in value of interest rate swap	2,523						2,523
Adjustments to carry redeemable Class A units at redemption value	(44,998)				(44,998)
Redeemable partnership units' share of above adjustments	(8,299)						(8,299)
Preferred unit redemptions	(9,230)					(9,230)
Other	(869)					(1,364)	533	(38)
Ending balance, Value at Mar. 31, 2013	$ 8,020,610			$ 1,277,719	$ 7,175,406	$ (1,479,296)	$ 120,953	$ 925,828
Ending balance, Units at Mar. 31, 2013				52,685	186,935