Consolidated Statements of Changes in Equity (USD $) In Thousands, unless otherwise specified	Total	Real Estate Fund [Member]	All Other Except Real Estate Fund [Member]	Preferred Units [Member]	Class A Units Held By Vornado [Member]	Earnings Less Than Distributions	Accumulated Other Comprehensive Income (Loss)	Non-controlling Interests	Non-controlling Interests Real Estate Fund [Member]	Non-controlling Interests All Other Except Real Estate Fund [Member]
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	643,013					622,370		20,643
Net income attributable to redeemable partnership units	(47,364)					(47,364)
Distributions to Vornado, value	(381,382)					(381,382)
Distributions to preferred unitholders, value	(47,905)					(47,905)
Proceeds from the issuance of units, units				9,850
Proceeds from the issuance of units, value	239,037			239,037
Class A units issued to Vornado:
Upon redemption of redeemable Class A units, at redemption value, units					435
Upon redemption of Class A units, at redemption value, value	38,220				38,220
Under Vornado's Omnibus Share plan, units					369
Under Vornado's Omnibus Share plan, value	21,221				21,618	(397)
Under Vornado's dividend reinvestment plan, units					15
Under Vornado's dividend reinvestment plan, value	1,330				1,330
Contributions:
Contributions		109,241	364						109,241	364
Distributions:
Distributions		(22,713)	(15,604)						(22,713)	(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					10
Deferred compensation units and options, value	7,866				7,866
Change in unrealized net loss on securities available-for-sale	(120,334)						(120,334)
Pro rata share of other comprehensive income (loss) of nonconsolidated subsidiaries	26,477						26,477
Change in value of interest rate swap	(42,458)						(42,458)
Adjustment to carry redeemable Class A units at redemption value	114,628				114,628
Redeemable partnership units' share of above adjustments	8,957						8,957
Discount on redemption of preferred units	5,000					5,000
Other	(5,030)			(105)	(4,518)	149	(5,114)	4,558
Ending balance, value at Sep. 30, 2011	7,362,969			1,021,855	7,119,354	(1,330,405)	(59,019)	611,184
Ending balance, units at Sep. 30, 2011				42,187	184,496
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	602,648					571,720		30,928
Net income attributable to redeemable partnership units	(40,595)					(40,595)
Distributions to Vornado, value	(384,353)					(384,353)
Distributions to preferred unitholders, value	(56,187)					(56,187)
Proceeds from the issuance of units, units				12,000
Proceeds from the issuance of units, value	291,144			291,144
Redemption of preferred units, units				(3,000)
Redemption of preferred units, value	(75,000)			(75,000)
Class A units issued to Vornado:
Upon redemption of redeemable Class A units, at redemption value, units					624
Upon redemption of Class A units, at redemption value, value	51,216				51,216
Under Vornado's Omnibus Share plan, units					414
Under Vornado's Omnibus Share plan, value	(7,458)				8,931	(16,389)
Under Vornado's dividend reinvestment plan, units					15
Under Vornado's dividend reinvestment plan, value	1,270				1,270
Contributions:
Contributions		120,606	140						120,606	140
Distributions:
Distributions		(44,910)	(10)						(44,910)	(10)
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	10,670				11,009	(339)
Change in unrealized net loss on securities available-for-sale	(202,167)						(202,167)
Pro rata share of other comprehensive income (loss) of nonconsolidated subsidiaries	(38,861)						(38,861)
Change in value of interest rate swap	(8,868)						(8,868)
Adjustment to carry redeemable Class A units at redemption value	(63,657)				(63,657)
Redeemable partnership units' share of above adjustments	15,717						15,717
Discount on redemption of preferred units	11,700					11,700
Other	(2,638)			0		(2,971)	343	(10)
Ending balance, value at Sep. 30, 2012	$ 7,688,854			$ 1,237,699	$ 7,143,505	$ (1,319,118)	$ (160,107)	$ 786,875
Ending balance, units at Sep. 30, 2012				51,185	186,143