Real Estate Acquisitions And Discontinued Operations (Unaudited Pro Forma Combined Condensed Statements Of Operations Information) (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Real Estate Acquisitions And Discontinued Operations [Abstract]
Real estate revenues	$ 76,823,000	$ 74,471,000	$ 231,370,000	$ 221,135,000
Income from continuing operations	3,283,000	4,046,000	11,330,000	10,784,000
Net income	$ 63,585,000	$ 7,578,000	$ 76,268,000	$ 29,665,000
Diluted earnings per share	$ 0.96	$ 0.12	$ 1.15	$ 0.48

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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