Noncontrolling Interests and Redeemable Noncontrolling Interests (Details 3) (USD $) In Thousands, unless otherwise specified	9 Months Ended			9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 PJV Units [Member]	Sep. 30, 2012 PJV Units [Member]	Sep. 30, 2013 Noncontrolling Interests	Dec. 31, 2012 Noncontrolling Interests	Sep. 30, 2013 Third Party Interests [Member]	Dec. 31, 2012 Third Party Interests [Member]	Sep. 30, 2013 Other Consolidated Subsidiaries [Member]	Dec. 31, 2012 Other Consolidated Subsidiaries [Member]	Sep. 30, 2013 Kirkwood Mall [Member]	Apr. 08, 2013 Kirkwood Mall [Member]	Sep. 30, 2013 Louisville Outlet Shoppes [Member]	Sep. 30, 2013 Outlet Shoppes at El Paso [Member]	Sep. 30, 2013 Triangle Town Member LLC [Member]
Noncontrolling Interest [Line Items]
Percentage of Equity Interest in Real Estate Property												51.00%		65.00%	75.00%	50.00%
Redeemable Noncontrolling Interest, Equity, Carrying Amount	$ 37,170		$ 464,082					$ 30,537	$ 33,835	$ 6,633	$ 6,413
Noncontrolling interests						165,023	192,404	143,023	128,908	22,000	63,496
Business Acquisition, Purchase Price Allocation, Liabilities Assumed													40,368
Increase (Decrease) in Redeemable Noncontrolling Preferred Joint Venture Interest
Beginning Balance	423,834			423,834	423,834
Net income attributable to redeemable noncontrolling preferred joint venture interest				14,637	15,486
Distributions to redeemable noncontrolling preferred joint venture interest				(19,894)	(15,486)
Reduction to preferred liquidation value of PJV units				(10,000)
Redemption of noncontrolling preferred joint venture interest	0	9,836		(408,577)
Ending Balance	$ 0			$ 0	$ 423,834