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	338,492					314,174		24,318
Net income attributable to redeemable partnership units	(24,355)					(24,355)
Distributions to Vornado	(256,119)					(256,119)
Distributions to preferred unitholders	(35,574)					(35,574)
Class A units issued to Vornado:
Upon redemption of redeemable Class A units, at redemption value, Units					303
Upon redemption of redeemable Class A units, at redemption value, Value	24,976				24,976
Under Vornado's Omnibus Share plan, Units					412
Under Vornado's Omnibus Share plan, Value	(7,573)				8,816	(16,389)
Under Vornado's dividend reinvestment plan, Units					10
Under Vornado's dividend reinvestment plan, Value	843				843
Contributions:
Contributions		108,319	30						108,319	30
Distributions:
Distributions		(44,910)							(44,910)
Conversion of Series A preferred units to Class A units, Units				(2)	3
Conversion of Series A preferred units to Class A units, Value				(105)	105
Deferred compensation units and options, Units					7
Deferred compensation units and options, Value	8,145				8,484	(339)
Change in unrealized net gain (loss) on available-for-sale securities	(220,525)						(220,525)
Pro rata share of other comprehensive loss of nonconsolidated subsidiaries	(26,254)						(26,254)
Change in value of interest rate swap	(6,002)						(6,002)
Adjustments to carry redeemable Class A units at redemption value	(110,581)				(110,581)
Redeemable partnership unit's share of above adjustments	15,894						15,894
Preferred unit redemptions	0
Other	372					2	373	(3)
Ending balance, Value at Jun. 30, 2012	7,273,625			1,021,555	7,067,274	(1,420,304)	(162,785)	767,885
Ending balance, Units at Jun. 30, 2012				42,185	185,815
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	471,248					445,032		26,216
Net income attributable to redeemable partnership units	(23,916)					(23,916)
Distributions to Vornado	(272,825)					(272,825)
Distributions to preferred unitholders	(42,070)					(42,070)
Issuance of Series L preferred units, Units				12,000
Issuance of Series L preferred units, Value	290,536			290,536
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					180
Upon redemption of redeemable Class A units, at redemption value, Value	14,980				14,980
Under Vornado's Omnibus Share plan, Units					62
Under Vornado's Omnibus Share plan, Value	3,567				3,567
Under Vornado's dividend reinvestment plan, Units					11
Under Vornado's dividend reinvestment plan, Value	903				903
Contributions:
Contributions		18,781	15,186						18,781	15,186
Distributions:
Distributions		(43,145)	(120,051)						(43,145)	(120,051)
Conversion of Series A preferred units to Class A units, Units				(2)	3
Conversion of Series A preferred units to Class A units, Value				(90)	90
Deferred compensation units and options, Value	4,481				4,786	(305)
Change in unrealized net gain (loss) on available-for-sale securities	169,138						169,138
Pro rata share of other comprehensive loss of nonconsolidated subsidiaries	(23,354)						(23,354)
Change in value of interest rate swap	14,560						14,560
Adjustments to carry redeemable Class A units at redemption value	(29,393)				(29,393)
Redeemable partnership unit's share of above adjustments	(9,034)						(9,034)
Preferred unit redemptions	(1,130)					(1,130)
Deconsolidation of partially owned entity	(165,427)							(165,427)
Other	(2,683)				(25)	(3,154)	530	(34)
Ending balance, Value at Jun. 30, 2013	$ 7,921,227			$ 1,277,455	$ 7,197,786	$ (1,471,643)	$ 132,894	$ 784,735
Ending balance, Units at Jun. 30, 2013				52,683	186,991