Consolidated Statements of Changes in Equity (USD $) In Thousands, unless otherwise specified	Total USD ($)	Real Estate Fund [Member] USD ($)	All Other Except Real Estate Fund [Member] USD ($)	Preferred Units [Member] USD ($)	Class A Units Owned by Vornado [Member]	Common Stock Including Additional Paid in Capital [Member] USD ($)	Earnings Less Than Distributions USD ($)	Accumulated Other Comprehensive Income (Loss) USD ($)	Non-controlling Interests USD ($)	Non-controlling Interests Real Estate Fund [Member] USD ($)	Non-controlling Interests All Other Except Real Estate Fund [Member] USD ($)
Beginning balance, value at Dec. 31, 2010	$ 6,830,405			$ 783,088		$ 6,940,045	$ (1,480,876)	$ 73,453	$ 514,695
Beginning balance, units at Dec. 31, 2010				32,340	183,662
Net income	445,821						444,471		1,350
Net income attributable to redeemable partnership units	(31,808)						(31,808)
Distributions to Vornado	(126,936)						(126,936)
Distributions to preferred unitholders	(13,559)						(13,559)
Class A Units Issued To Vornado:
Upon redemption of Class A units, at redemption value, units					320
Upon redemption of Class A units, at redemption value, value	27,539					27,539
Under Vornado's Omnibus share plan, units					240
Under Vornado's Omnibus share plan, value	14,639					15,037	(398)
Under Vornado's Dividend Reinvestment Plan, units					5
Under Vornado's Dividend Reinvestment plan, value	434					434
Contributions:
Contributions		92,068	170							92,068	170
Distributions:
Distributions		(11,027)								(11,027)
Conversion Of Series A preferred units to Class A units, units				(1)	2
Conversion of Series A preferred units to Class A units, value	0			(50)		50
Deferred compensation units and options, units					11
Deferred compensation units and options, value	2,370					2,370
Change in unrealized net gain on securities available-for-sale	68,039							68,039
Pro rata share of other comprehensive loss of nonconsolidated subsidiaries	(3,791)							(3,791)
Change in value of interest rate swap	(7,146)							(7,146)
Adjustment to carry redeemable Class A units at redemption value	(42,227)					(42,227)
Other	(147)			(105)		(173)	113	59	(41)
Ending balance, value at Mar. 31, 2011	7,244,844			782,933		6,943,075	(1,208,993)	130,614	597,215
Ending balance, units at Mar. 31, 2011				32,339	184,240
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 Class A units, at redemption value, units					158
Upon redemption of 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
Adjustment to carry redeemable Class A units at redemption value	(96,061)					(96,061)
Redeemable partnership units' share of above adjustments	433							433
Other	(125)			0			0	(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