Investment in Unconsolidated Entities (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended				6 Months Ended	12 Months Ended			3 Months Ended		6 Months Ended			6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2013 Retail Property property	Dec. 31, 2012 Retail Property property	Dec. 31, 2012 Malls property	Mar. 22, 2012 The Mills acquisition property	Jun. 30, 2013 Equity Method Investments	Jun. 30, 2012 Equity Method Investments	Jun. 30, 2013 Equity Method Investments	Jun. 30, 2012 Equity Method Investments	Dec. 31, 2012 Equity Method Investments	Jun. 30, 2013 Equity Method Investments Maximum
Schedule of Equity Method Investments
Number of income-producing properties										9
Number of properties disposed							1	3	1
Assets:
Investment properties, at cost	$ 34,636,100		$ 34,636,100		$ 34,252,521						$ 14,621,714		$ 14,621,714		$ 14,607,291
Less - accumulated depreciation	9,544,943		9,544,943		9,068,388						5,027,179		5,027,179		4,926,511
Investment properties, net	25,091,157		25,091,157		25,184,133						9,594,535		9,594,535		9,680,780
Cash and cash equivalents	1,095,829	638,499	1,095,829	638,499	1,184,518	798,650					551,059		551,059		619,546
Tenant receivables and accrued revenue, net	491,388		491,388		521,301						225,178		225,178		252,774
Investment in unconsolidated entities, at equity	1,958,503		1,958,503		2,108,966						38,958		38,958		39,589
Deferred costs and other assets	1,474,421		1,474,421		1,570,734						707,343		707,343		438,399
Total assets	32,015,137		32,015,137		32,586,606						11,117,073		11,117,073		11,031,088
Liabilities and Partners' Deficit:
Mortgages and unsecured indebtedness	22,687,622		22,687,622		23,113,007						11,964,864		11,964,864		11,584,863
Accounts payable, accrued expenses, intangibles, and deferred revenue	1,273,211		1,273,211		1,374,172						596,283		596,283		672,483
Other liabilities	231,774		231,774		303,588						657,205		657,205		447,132
Total liabilities	25,028,872		25,028,872		25,515,511						13,218,352		13,218,352		12,704,478
Preferred units											67,450		67,450		67,450
Partners' deficit											(2,168,729)		(2,168,729)		(1,740,840)
Total liabilities and equity	32,015,137		32,015,137		32,586,606						11,117,073		11,117,073		11,031,088
Our Share of:
Partners' deficit											(992,395)		(992,395)		(799,911)
Add: Excess Investment											2,114,633		2,114,633		2,184,133
Our net Investment in unconsolidated entities, at equity											1,122,238		1,122,238		1,384,222
Life of joint ventures with excess investment																40 years
Revenue:
Minimum rent	778,159	746,198	1,556,066	1,448,295							399,391	363,541	793,544	721,517
Overage rent	40,248	31,427	77,947	59,107							40,014	36,064	87,781	84,620
Tenant reimbursements	353,163	330,470	692,132	636,857							187,151	165,623	371,550	332,153
Other income	33,179	51,624	63,933	102,142							39,528	36,597	81,602	86,934
Total revenue	1,236,563	1,188,066	2,451,621	2,307,035							666,084	601,825	1,334,477	1,225,224
Operating Expenses:
Property operating	117,479	116,018	227,388	220,758							123,296	111,967	239,165	226,801
Depreciation and amortization	318,638	311,863	635,272	596,972							126,701	122,475	254,386	249,453
Real estate taxes	109,409	106,777	219,114	205,479							50,072	42,450	104,778	87,550
Repairs and maintenance	27,107	26,665	56,832	52,307							16,339	15,427	32,503	29,851
Advertising and promotion	29,360	28,549	50,619	49,648							14,103	12,688	30,023	27,895
Provision for (Recovery of) credit losses	(1,301)	2,906	1,433	6,451							336	(793)	1,580	399
Other	18,604	21,124	36,605	37,788							36,496	38,549	72,181	92,043
Total operating expenses	671,673	663,739	1,329,043	1,265,987							367,343	342,763	734,616	713,992
Operating Income	564,890	524,327	1,122,578	1,041,048							298,741	259,062	599,861	511,232
Interest expense	(279,966)	(288,560)	(564,991)	(546,636)							(154,508)	(148,980)	(301,994)	(302,690)
Income from Continuing Operations											144,233	110,082	297,867	208,542
Loss from operations of discontinued joint venture interests											(26)	(5,280)	(346)	(18,791)
Gain on disposal of discontinued operations, net											18,356		18,356
Net Income											162,563	104,802	315,877	189,751
Third-Party Investors' Share of Net Income											94,949	56,787	178,715	96,800
Our Share of Net Income											67,614	48,015	137,162	92,951
Amortization of Excess Investment											(24,853)	(18,749)	(49,682)	(33,333)
Income from Unconsolidated Entities											$ 42,761	$ 29,266	$ 87,480	$ 59,618