Earnings Per Share of the Parent Company (Computations of Basic and Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Earnings Per Share of the Parent Company
Net income available to common stockholders	$ 3,638	$ 4,199	$ 9,168	$ 8,499
Less: net income allocable and distributions in excess of earnings to participating securities	(279)	(192)	(577)	(383)
Net income attributable to common stockholders - basic	3,359	4,007	8,591	8,116
Add: net income allocable and distributions in excess of earnings to dilutive participating securities		192		383
Add: net income attributable to noncontrolling interests in operating partnership	82	109	207	237
Net income attributable to common stockholders and participating securities	$ 3,441	$ 4,308	$ 8,798	$ 8,736
Basic	129,858,098	109,707,274	129,815,154	104,000,339
Unvested restricted stock.		1,230,236		1,259,753
Operating partnership and LTIP units	2,982,834	3,018,567	2,987,943	3,038,043
Diluted	132,840,932	113,956,077	132,803,097	108,298,135
Earnings Per Share, Basic and Diluted	$ 0.03	$ 0.04	$ 0.07	$ 0.08

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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