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Real Estate Investments (Details Textuals 1) (USD $) In Millions, unless otherwise specified | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2011 | Jul. 29, 2011 sqft | Jun. 27, 2011 Three Greentree Center [Member] sqft
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Net rentable square feet of properties sold |  | 347,620 | 69,300
Sales price of properties sold |  | $ 86.7 | $ 5.9
Lease percentage of sold property |  |  | 13.90%
Gain on sale of ownership interest | $ 2.8 |  |
Remaining Ownership Interest in Real Estate Properties | 11.00% |  |
Number of properties with ownership interest | 3 |  |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + Details
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