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, 2008	$ 6,214,652			$ 823,807		$ 6,032,171	$ (1,047,340)	$ (6,899)	$ 412,913
Beginning balance, units at Dec. 31, 2008				33,954	155,286
Net income	128,450						131,289		(2,839)
Net (income) attributable to redeemable partnership unit	(25,120)						(25,120)
Distribution to Vornado, units					6,441
Distributions to Vornado	(262,397)					285,596	(547,993)
Distributions to preferred unitholders	(57,076)						(57,076)
Proceeds from the issuance of units, Units					17,250
Proceeds from the issuance of units, Value	710,226					710,226
Class A Units Issued To Vornado:
Upon redemption of Class A units, at redemption value, Units					1,768
Upon redemption of Class A units, at redemption value, Value	90,955					90,955
Under Vornado's Omnibus share plan, units					468
Under Vornado's Omnibus share plan, value	(29,638)					1,717	(31,355)
Limited partner's distribution:
Conversion Of Series A preferred units to Class A units, Units				(2)	2
Conversion of Series A preferred units to Class A units, Value	0			(89)		89
Deferred compensation units and options, Units					(1)
Deferred compensation units and options, Value	13,092					13,092
Change in unrealized net gain on securities available-for-sale	6,147							6,147
Sale of securities available-for-sale	7,715							7,715
Pro rata share of other comprehensive income of nonconsolidated subsidiaries	22,052							22,052
Voluntary surrender of equity awards on March 31, 2009	32,588					32,588
Change in value of interest rate swap	0
Adjustment to carry redeemable Class A units at redemption value	(167,049)					(167,049)
Allocation of cash paid to the equity component upon repurchase of convertible senior debentures due to Vornado	(30,159)					(30,159)
Other	(5,032)			(32)		(1,001)	4	(566)	(3,437)
Ending balance, Value at Dec. 31, 2009	6,649,406			823,686		6,968,225	(1,577,591)	28,449	406,637
Ending balance, units at Dec. 31, 2009				33,952	181,214
Net income	708,031						703,111		4,920
Net (income) attributable to redeemable partnership unit	(55,228)						(55,228)
Distributions to Vornado	(474,299)						(474,299)
Distributions to preferred unitholders	(55,669)						(55,669)
Redemption of preferred units, units				(1,600)
Redemption of preferred units, Value	(35,600)			(39,982)			4,382
Class A Units Issued To Vornado:
Upon redemption of Class A units, at redemption value, Units					1,548
Upon redemption of Class A units, at redemption value, Value	126,764					126,764
Under Vornado's Omnibus share plan, units					812
Under Vornado's Omnibus share plan, value	(261)					25,323	(25,584)
Under Vornado's Dividend Reinvestment Plan, units					22
Under Vornado's Dividend Reinvestment plan, Value	1,657					1,657
Limited partners' contributions:
Limited partners' contribution		93,583	8,783							93,583	8,783
Limited partner's distribution:
Conversion Of Series A preferred units to Class A units, Units				(12)	18
Conversion of Series A preferred units to Class A units, Value	0			(616)		616
Deferred compensation units and options, Units					48
Deferred compensation units and options, Value	9,347					9,347
Change in unrealized net gain on securities available-for-sale	46,447							46,447
Sale of securities available-for-sale	(13,160)							(13,160)
Pro rata share of other comprehensive income of nonconsolidated subsidiaries	11,853							11,853
Change in value of interest rate swap	0
Adjustment to carry redeemable Class A units at redemption value	(191,826)					(191,826)
Other	577					(61)	2	(136)	772
Ending balance, Value at Dec. 31, 2010	6,830,405			783,088		6,940,045	(1,480,876)	73,453	514,695
Ending balance, units at Dec. 31, 2010				32,340	183,662
Net income	740,000						718,214		21,786
Net (income) attributable to redeemable partnership unit	(55,912)						(55,912)
Distributions to Vornado	(508,745)						(508,745)
Distributions to preferred unitholders	(65,694)						(65,694)
Proceeds from the issuance of units, Units				9,850
Proceeds from the issuance of units, Value	238,842			238,842
Class A Units Issued To Vornado:
Upon redemption of Class A units, at redemption value, Units					798
Upon redemption of Class A units, at redemption value, Value	64,830					64,830
Under Vornado's Omnibus share plan, units					590
Under Vornado's Omnibus share plan, value	10,439					23,728	(13,289)
Under Vornado's Dividend Reinvestment Plan, units					21
Under Vornado's Dividend Reinvestment plan, Value	1,772					1,772	0
Limited partners' contributions:
Limited partners' contribution		203,407	778							203,407	778
Limited partner's distribution:
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders		(49,422)	(15,604)							(49,422)	(15,604)
Conversion Of Series A preferred units to Class A units, Units				(3)	5
Conversion of Series A preferred units to Class A units, Value	0			(165)		165
Deferred compensation units and options, Units					4
Deferred compensation units and options, Value	10,085					10,608	(523)
Change in unrealized net gain on securities available-for-sale	46,177							46,177
Sale of securities available-for-sale	(9,540)							(9,540)
Pro rata share of other comprehensive income of nonconsolidated subsidiaries	12,859							12,859
Change in value of interest rate swap	(43,704)							(43,704)
Adjustment to carry redeemable Class A units at redemption value	98,092					98,092
Redeemable partnership units' share of above adjustments	(271)							(271)
Other	(347)			(105)		(4,609)	5,121	(5,245)	4,491
Ending balance, Value at Dec. 31, 2011	$ 7,508,447			$ 1,021,660		$ 7,134,631	$ (1,401,704)	$ 73,729	$ 680,131
Ending balance, units at Dec. 31, 2011				42,187	185,080