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Discontinued Operations (Details Textuals) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2011 Property Tenants | Sep. 30, 2010 Property Tenants | Sep. 30, 2011 Property Tenants Year sqft | Sep. 30, 2010 Tenants Property
Discontinued Operations (Textuals) [Abstract] |  |  |  |
Number of properties sold | 1 | 9 | 1 | 9

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- Definition Number of properties sold. + Details
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