Real Estate Investments (Details 3) (USD $) In Thousands, except Per Share data	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Supplemental Pro Forma Operating Data [Abstract]
Pro forma revenues		$ 142,920		$ 433,734
Pro forma loss from continuing operations		(7,408)		(19,279)
Pro forma net loss available to common shareholders		$ (8,973)		$ (17,862)
Loss per common share from continuing operations :
Loss from continuing operations attributable to common shareholders, Basic	$ 0.03	$ (0.06)	$ (0.08)	$ (0.20)
Basic -- as pro forma		$ (0.06)		$ (0.20)
Loss from continuing operations attributable to common shareholders, Diluted	$ 0.03	$ (0.06)	$ (0.08)	$ (0.20)
Diluted - as pro forma		$ (0.06)		$ (0.20)
Loss per common share:
Basic -- as reported	$ 0.03	$ (0.06)	$ (0.05)	$ (0.14)
Basic -- as pro forma		$ (0.06)		$ (0.14)
Diluted - as reported	$ 0.03	$ (0.06)	$ (0.05)	$ (0.14)
Diluted - as pro forma		$ (0.06)		$ (0.14)

Earnings per common share from continuing operations.

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