Investment in Unconsolidated Entities (Details 2) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended
May 28, 2014 Unconsolidated property interests property	Mar. 31, 2014 Arizona Mills	Jan. 30, 2014 Arizona Mills
Acquisitions
Ownership interests acquired (as a percent)			50.00%
Gain due to acquisition of controlling interest		$ 2.7
Ownership interest after acquisition (as a percent)			100.00%
Number of unconsolidated properties in the spin-off of Washington Prime	10

Represents the number of properties merged under spin off into publicly traded real estate investment trust.

No definition available.

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- Details

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

+ Details

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- Definition

In a business combination achieved in stages, this element represents the amount of net gain (loss) recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)(2)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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