Investments in Unconsolidated Entities (Details) (USD $)	12 Months Ended					12 Months Ended		0 Months Ended		12 Months Ended	1 Months Ended	12 Months Ended													12 Months Ended		12 Months Ended	0 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Construction and other related party loans	Dec. 31, 2012 Construction and other related party loans	Dec. 31, 2012 The Shops at Mission Viejo	Dec. 31, 2012 IMI Woodfield Mall	May 21, 2012 Klepierre	Mar. 14, 2012 Klepierre	Dec. 31, 2012 IMI Joint Venture Woodfield Mall	Jan. 31, 2013 IMI Joint Venture The Shops at Mission Viejo	Dec. 31, 2012 IMI Joint Venture The Shops at Mission Viejo	Dec. 31, 2012 IMI Joint Venture IMI Woodfield Mall	Dec. 31, 2012 IMI Joint Venture IMI The Shops at Mission Viejo	Dec. 31, 2013 United States property	Dec. 31, 2012 United States property	Dec. 31, 2013 Japan property	Dec. 31, 2012 Japan property	Dec. 31, 2013 South Korea property	Dec. 31, 2012 South Korea property	Dec. 31, 2013 Mexico property	Dec. 31, 2012 Mexico property	Dec. 31, 2013 Malaysia property	Dec. 31, 2012 Malaysia property	Dec. 31, 2013 Italy property	Jan. 09, 2012 Italy GCI property	Dec. 31, 2013 Europe property	Jan. 09, 2012 Europe GCI	Dec. 31, 2013 Europe Klepierre
Schedule of Equity Method Investments
Number of properties															73	78	9	8	3	2	1	1	1	1
Number of outlets in which interest acquired																									2		5
Number of properties sold																										45
Joint venture ownership percentage									28.70%																				28.90%
Joint venture ownership percentage after transactions								28.90%		50.00%		51.00%	50.00%	49.00%
Loans to related party				$ 140,300,000	$ 25,400,000
Joint venture ownership percentage before transaction						100.00%	100.00%
Gain due to formation of joint venture						0																						28,800,000
Aggregate face amount of mortgage notes										425,000,000	295,000,000
Interest rate on mortgage loan (as a percent)										4.50%	3.61%
Distribution from joint venture financing proceeds	$ 179,054,000	$ 151,398,000	$ 112,977,000								$ 149,700,000