Significant Accounting Policies (Details 9) $ in Thousands		3 Months Ended
	May. 28, 2014 USD ($) property	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)
Strip Center Business and Small Malls
Discontinued Operations
Number of properties merged under spin off into Washington Prime, an independent publicly traded REIT | property	98
Amount of retained proceeds from recently completed unsecured debt and mortgage debt as part of the spin-off	$ 1,000,000
Summarized financial information for discontinued operations
TOTAL REVENUE			$ 157,969
Property operating			26,140
Depreciation and amortization			45,968
Real estate taxes			19,948
Repairs and maintenance			7,150
Advertising and promotion			1,952
Provision for credit losses			786
Other			1,118
Total operating expenses			103,062
OPERATING INCOME			54,907
Interest expense			(13,917)
Income and other taxes			(75)
Income from unconsolidated entities			345
Gain upon acquisition of controlling interests and sale or disposal of assets and interest in unconsolidated entities, net			242
CONSOLIDATED NET INCOME			41,502
Net income attributable to noncontrolling interests			5,989
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS			35,513
Additional disclosures
Capital expenditures on a cash basis			$ 24,800
Washington Prime Group Inc
Additional disclosures
Transition services fees earned		$ 1,300
Washington Prime Group Inc | Strip Center Business and Small Malls
Additional disclosures
Term of property management agreement	2 years
Renewal term of property management agreement	1 year
Termination period of property management agreement	2 years
Period of prior written notice for termination of property management agreement	180 days
Termination period of transition services agreement	2 years
Minimum notice period for transition services agreement	180 days
Minimum notice period as percentage of original service period	50.00%
Exchange ratio of common shares for entity's stockholders to receive under spin off	0.50
Washington Prime Group Inc | Minimum
Additional disclosures
Annual fixed rate property management fees (as a percent)	2.50%
Washington Prime Group Inc | Maximum
Additional disclosures
Annual fixed rate property management fees (as a percent)	4.00%
Washington Prime Group LP | Strip Center Business and Small Malls
Additional disclosures
Exchange ratio of common units for entity's stockholders to receive under spin off	0.50