Investment in Unconsolidated Entities (Details 3) $ / shares in Units, $ in Thousands				1 Months Ended	3 Months Ended
	Apr. 13, 2015 USD ($) property	Feb. 24, 2015 USD ($)	Jan. 15, 2015	Dec. 31, 2014 USD ($)	Mar. 31, 2015 USD ($) property $ / shares shares	Mar. 31, 2014 USD ($)
Schedule of Equity Method Investments
Joint venture ownership percentage					18.30%
Share of net income, net of amortization of our excess investment					$ 64,872	$ 57,078
Equity investment				$ 2,378,800	2,158,205
Gain upon acquisition of controlling interests and sale or disposal of assets and interests in unconsolidated entities, net					$ 206,927	2,655
Seritage Growth Properties | Forecast
Schedule of Equity Method Investments
Payments to acquire equity method investment	$ 33,000
Houston Galleria
Schedule of Equity Method Investments
Joint venture ownership percentage		50.40%
Hudson's Bay Company (HBC) Joint Venture | Forecast
Schedule of Equity Method Investments
Joint venture ownership percentage					20.00%
Hudson's Bay Company (HBC) Joint Venture | Maximum | Forecast
Schedule of Equity Method Investments
Contribution to form joint venture					$ 178,500
Contributions for improvements to properties					$ 100,000
Hudson's Bay Company (HBC) Joint Venture | Hudson Bay Company | Forecast
Schedule of Equity Method Investments
Number of properties contributed to form joint venture | property					42
Joint venture ownership percentage					80.00%
Sears Joint Venture
Schedule of Equity Method Investments
Contribution to form joint venture	$ 114,000
Joint venture ownership percentage	50.00%
Sears Joint Venture | Minimum
Schedule of Equity Method Investments
Percentage of property space subject to recapture	50.00%
Sears Joint Venture | Sears
Schedule of Equity Method Investments
Number of properties contributed to form joint venture | property	10
Joint venture ownership percentage	50.00%
Klepierre
Schedule of Equity Method Investments
Joint venture ownership percentage				28.90%
Klepierre | Corio
Schedule of Equity Method Investments
Ordinary share conversion ratio			1.14
Gain upon acquisition of controlling interests and sale or disposal of assets and interests in unconsolidated entities, net					$ 206,900
McArthurGlen Group
Schedule of Equity Method Investments
Number of properties | property					5
Equity investment				$ 677,100	$ 581,400
McArthurGlen Group | Minimum
Schedule of Equity Method Investments
Joint venture ownership percentage					45.00%
McArthurGlen Group | Maximum
Schedule of Equity Method Investments
Joint venture ownership percentage					90.00%
McArthurGlen Group | Roermond Designer Outlet
Schedule of Equity Method Investments
Joint venture ownership percentage				90.00%
Europe | Klepierre
Schedule of Equity Method Investments
Shares owned | shares					57,634,148
Joint venture ownership percentage			28.90%		18.30%
Quoted market price per share (in dollars per share) | $ / shares					$ 49.48
Share of net income, net of amortization of our excess investment					$ 6,100	4,800
Total revenues					332,500	367,300
Total operating income					141,600	166,700
Consolidated net income					$ 72,000	$ 52,900
Europe | McArthurGlen Group | Premium Outlets
Schedule of Equity Method Investments
Number of properties | property					5
Europe | McArthurGlen Group | Development project
Schedule of Equity Method Investments
Number of properties | property					1
Mortgage Maturing 2017 | McArthurGlen Group | Roermond Designer Outlet
Schedule of Equity Method Investments
Debt refinanced				$ 85,100
Interest rate on debt (as a percent)				5.12%
Mortgage Maturing 2021 | McArthurGlen Group | Roermond Designer Outlet
Schedule of Equity Method Investments
Debt issued to refinance previous mortgage				$ 218,900
Interest rate on debt (as a percent)				1.86%
Mortgages | Houston Galleria
Schedule of Equity Method Investments
Debt refinanced		$ 821,000
Interest rate on debt (as a percent)		5.44%
Mortgage Maturing 2025 | Houston Galleria
Schedule of Equity Method Investments
Debt issued to refinance previous mortgage		$ 1,200,000
Interest rate on debt (as a percent)		3.55%