Consolidated Statements of Equity (USD $) Share data in Thousands	Total	Series D Preferred Shares of Beneficial Interest [Member]	Preferred Shares of Beneficial Interest [Member]	Preferred Shares of Beneficial Interest [Member] Series D Preferred Shares of Beneficial Interest [Member]	Common Shares of Beneficial Interest [Member]	Common Shares of Beneficial Interest [Member] Series D Preferred Shares of Beneficial Interest [Member]	Additional Paid-In Capital [Member]	Additional Paid-In Capital [Member] Series D Preferred Shares of Beneficial Interest [Member]	Accumulated Distributions in Excess of Net Income [Member]	Accumulated Distributions in Excess of Net Income [Member] Series D Preferred Shares of Beneficial Interest [Member]	Accumulated Other Comprehensive Income(loss) [Member]	Accumulated Other Comprehensive Income(loss) [Member] Series D Preferred Shares of Beneficial Interest [Member]	Non-Controlling Interests [Member]	Non-Controlling Interests [Member] Series D Preferred Shares of Beneficial Interest [Member]
Beginning balance at Dec. 31, 2012	$ 469,264,000		$ 120,500,000		$ 33,019,000		$ 618,426,000		$ (317,385,000)		$ (50,000)		$ 14,754,000
Beginning balance, shares at Dec. 31, 2012			4,820		33,019
Net income attributable to Winthrop Realty Trust	22,120,000		0		0		0		22,120,000		0		0
Net loss attributable to non-controlling interests	(1,424,000)		0		0		0		0		0		(1,424,000)
Contributions from non-controlling interests	535,000		0		0		0		0		0		535,000
Purchase of non-controlling interests	(150,000)		0		0		103,000		0		0		(253,000)
Dividends declared on Common Shares of Beneficial Interest ($0.325 per share)	(10,736,000)		0		0		0		(10,736,000)		0		0
Dividends declared on Series D Preferred Shares ($1.15625 per share)		(5,573,000)		0		0		0		(5,573,000)		0		0
Dividends declared on Restricted Shares	(114,000)		0		0		0		(114,000)		0		0
Change in unrealized (loss) gain on interest rate derivatives	130,000		0		0		0		0		130,000		0
Stock issued pursuant to Dividend Reinvestment Plan	234,000		0		20,000		214,000		0		0		0
Stock issued pursuant to Dividend Reinvestment Plan, shares					20
Issuance of Restricted Shares, Value	0		0		0		0		0		0		0
Issuance of Restricted Shares					600
Amortization of Restricted Shares	211,000		0		0		211,000		0		0		0
Ending balance at Jun. 30, 2013	474,497,000		120,500,000		33,039,000		618,954,000		(311,688,000)		80,000		13,612,000
Ending balance, shares at Jun. 30, 2013			4,820		33,639
Beginning balance at Dec. 31, 2013	509,663,000		120,500,000		35,809,000		647,121,000		(322,432,000)		(124,000)		28,789,000
Beginning balance, shares at Dec. 31, 2013			4,820		36,401
Net income attributable to Winthrop Realty Trust	9,602,000		0		0		0		9,602,000		0		0
Net loss attributable to non-controlling interests	(3,423,000)		0		0		0		0		0		(3,423,000)
Distributions to non-controlling interests	(529,000)		0		0		0		0		0		(529,000)
Contributions from non-controlling interests	451,000		0		0		0		0		0		451,000
Increase in non-controlling interest due to consolidation of property	16,391,000		0		0		0		0		0		16,391,000
Decrease in non-controlling interest due to property sale	(3,764,000)		0		0		0		0		0		(3,764,000)
Dividends declared on Common Shares of Beneficial Interest ($0.325 per share)	(11,642,000)		0		0		0		(11,642,000)		0		0
Dividends declared on Series D Preferred Shares ($1.15625 per share)		(5,573,000)		0		0		0		(5,573,000)		0		0
Dividends declared on Restricted Shares	(192,000)		0		0		0		(192,000)		0		0
Change in unrealized (loss) gain on interest rate derivatives	(638,000)		0		0		0		0		(638,000)		0
Stock issued pursuant to Dividend Reinvestment Plan	178,000		0		16,000		162,000		0		0		0
Stock issued pursuant to Dividend Reinvestment Plan, shares					16
Amortization of Restricted Shares	1,331,000		0		0		1,331,000		0		0		0
Ending balance at Jun. 30, 2014	$ 511,855,000		$ 120,500,000		$ 35,825,000		$ 648,614,000		$ (330,237,000)		$ (762,000)		$ 37,915,000
Ending balance, shares at Jun. 30, 2014			4,820		36,417