Consolidated Statements of Changes in Equity (USD $) In Thousands	Total USD ($)	Preferred Units [Member] USD ($)	Class A Units Owned By Vornado [Member]	Common Stock Including Additional Paid in Capital [Member] USD ($)	Earnings Less Than Distributions [Member] USD ($)	Accumulated Other Comprehensive Income (Loss) [Member] USD ($)	Non-controlling Interests [Member] USD ($)	Real Estate Fund [Member] USD ($)	Real Estate Fund [Member] Non-controlling Interests [Member] USD ($)	All Other Except Real Estate Fund [Member] USD ($)	All Other Except Real Estate Fund [Member] Non-controlling Interests [Member] USD ($)
Beginning balance, value at Dec. 31, 2009	$ 6,649,406	$ 823,686		$ 6,968,225	$ (1,577,591)	$ 28,449	$ 406,637
Beginning balance, units at Dec. 31, 2009		33,952	181,214
Net income	309,755				308,561		1,194
Net (income) attributable to redeemable partnership units	(21,903)				(21,903)
Distributions to Vornado	(236,279)				(236,279)
Distributions to preferred unitholders	(28,533)				(28,533)
Class A Units Issued To Vornado:
Upon redemption of redeemable Class A units, at redemption value, units			495
Upon redemption of redeemable Class A units, at redemption value, value	35,711			35,711
Under Vornado's employees' share option plan, units			548
Under Vornado's employees' share option plan, value	(16,422)			9,011	(25,433)
Under Vornado's dividend reinvestment plan, units			12
Under Vornado's dividend reinvestment plan, value	802			802
Contributions:
Conversion Of Series A Preferred units To Class A units, units		(3)	4
Conversion of Series A preferred units to Class A units, value	0	(152)		152
Deferred compensation units and options, units			17
Deferred compensation units and options, value	3,906			3,906
Change in unrealized net gain on securities available-for-sale	25,531					25,531
Pro rata share of other comprehensive income of nonconsolidated subsidiaries	(15,965)					(15,965)
Change in value of interest rate swap and caps	0
Adjustment to carry redeemable Class A units at redemption value	(66,075)			(66,075)
Other	(1,021)			(60)	2	(418)	(545)
Ending balance, value at Jun. 30, 2010	6,638,913	823,534		6,951,672	(1,581,176)	37,597	407,286
Ending balance, units at Jun. 30, 2010		33,949	182,290
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	576,790				561,783		15,007
Net (income) attributable to redeemable partnership units	(40,539)				(40,539)
Distributions to Vornado	(254,099)				(254,099)
Distributions to preferred unitholders	(30,116)				(30,116)
Issuance of Series J preferred units, units		8,850
Issuance of Series J preferred units, value	214,538	214,538
Class A Units Issued To Vornado:
Upon redemption of redeemable Class A units, at redemption value, units			401
Upon redemption of redeemable Class A units, at redemption value, value	35,208			35,208
Under Vornado's employees' share option plan, units			343
Under Vornado's employees' share option plan, value	20,051			20,448	(397)
Under Vornado's dividend reinvestment plan, units			10
Under Vornado's dividend reinvestment plan, value	883			883
Contributions:
Contributions								109,241	109,241	364	364
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	(75)		75
Deferred compensation units and options, units			10
Deferred compensation units and options, value	5,122			5,122
Change in unrealized net gain on securities available-for-sale	40,844					40,844
Pro rata share of other comprehensive income of nonconsolidated subsidiaries	26,365					26,365
Change in value of interest rate swap and caps	(18,034)					(18,034)
Adjustment to carry redeemable Class A units at redemption value	(104,693)			(104,693)
Redeemable partnership units' share of above adjustments	(3,104)					(3,104)
Distributions to Limited Partners								(20,796)	(20,796)	(15,604)	(15,604)
Other	(5,302)	(105)		(4,518)	(10)	(5,045)	4,376
Ending balance, value at Jun. 30, 2011	$ 7,367,524	$ 997,446		$ 6,892,570	$ (1,244,254)	$ 114,479	$ 607,283
Ending balance, units at Jun. 30, 2011		41,189	184,428