Acquisitions, Dispositions, Leasing and Financing Activities - The Accompanying Unaudited Pro Forma Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Business Combinations [Abstract]
Total revenue	$ 101,465	$ 112,694	$ 76,049
Income from continuing operations	8,890	10,610	8,299
Net income attributable to Winthrop Realty Trust	$ 24,419	$ 17,519	$ 8,140
Per common share data - basic	$ 0.72	$ 0.53	$ 0.23
Per common share data - diluted	$ 0.72	$ 0.53	$ 0.23

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

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

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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