Significant Tenant (Details) (Lessee of real estate investments, Travel Centers of America LLC)	3 Months Ended
Mar. 31, 2013
Lessee of real estate investments \| Travel Centers of America LLC
Significant tenant disclosures
Percentage of real estate properties leased	38.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

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-Name Accounting Standards Codification

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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