Earnings per Common Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Income from continuing operations	$ 5,263	$ 5,694	$ 9,218	$ 10,528
Allocation of undistributed earnings to unvested restricted share awards	(142)	(167)	(192)	(342)
Adjusted income from continuing operations attributable to the controlling interests	5,121	5,527	9,026	10,186
Income from discontinued operations, including gain on sale of real estate, net of taxes	0	314	3,380	661
Allocation of undistributed earnings to unvested restricted share awards	0	(9)	(70)	(21)
Adjusted income from discontinuing operations attributable to the controlling interests	0	305	3,310	640
Adjusted net income attributable to the controlling interests	$ 5,121	$ 5,832	$ 12,336	$ 10,826
Weighted average shares outstanding - basic (in shares)	66,405	66,241	66,399	66,218
Effect of dilutive securities: Operating partnership units	117	117	117	117
Effect of dilutive securities: Employee stock options and restricted share awards	34	22	21	19
Weighted average shares outstanding - diluted (in shares)	66,556	66,380	66,537	66,354
Earnings per common share, basic, Continuing operations (in dollars per share)	$ 0.08	$ 0.08	$ 0.14	$ 0.15
Earnings per common share, basic, Discontinued operations (in dollars per share)	$ 0.00	$ 0.01	$ 0.05	$ 0.01
Net income per share (in dollars per share)	$ 0.08	$ 0.09	$ 0.19	$ 0.16
Earnings per common share, diluted, Continuing operations (in dollars per share)	$ 0.08	$ 0.08	$ 0.14	$ 0.15
Earnings per common share, diluted, Discontinued operations (in dollars per share)	$ 0.00	$ 0.01	$ 0.05	$ 0.01
Net income per share (in dollars per share)	$ 0.08	$ 0.09	$ 0.19	$ 0.16