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Significant Accounting Policies - Inv in non-consolidated REITs (Details) - USD ($) $ in Millions |  |  | 1 Months Ended
--- | --- | --- | ---
May 29, 2009 | Dec. 27, 2007 | May 31, 2009 | Dec. 31, 2007
East Wacker |  |  |  |
Investment in Sponsored REITs |  |  |  |
Preferred shares purchased |  | 965.75 |  | 965.75
Percentage of outstanding preferred shares purchased |  | 43.70% |  | 43.70%
Net cost of preferred shares purchased |  | $ 82.8 |  |
Grand Boulevard |  |  |  |
Investment in Sponsored REITs |  |  |  |
Preferred shares purchased | 175.5 |  | 175.5 |
Percentage of outstanding preferred shares purchased | 27.00% |  | 27.00% |
Net cost of preferred shares purchased | $ 15.0 |  |  |

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