Stockholders' Equity - Computation of basic and diluted earnings (loss) per common share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Weighted average Common Shares outstanding
Weighted average Common Shares outstanding	96,009,788	88,717,028
Nonvested shares	(1,857,536)	(1,822,692)
Weighted average Common Shares—Basic	94,152,252	86,894,336
Dilutive effect of restricted stock	1,299,287	1,282,722
Dilutive effect of employee stock purchase plan	133,893	205,378
Weighted average Common Shares outstanding—Diluted	95,585,432	88,382,436
Net Income (Loss)
Income from continuing operations	$ 7,732	$ 907
Noncontrolling interests’ share in net (income) loss	(111)	19
Income (loss) from continuing operations attributable to common stockholders	7,621	926
Discontinued operations	(3,769)	(1,925)
NET INCOME (LOSS) ATTRIBUTABLE TO COMMON STOCKHOLDERS	$ 3,852	$ (999)
Basic Earnings (Loss) Per Common Share
Income (loss) from continuing operations (in dollars per share)	$ 0.08	$ 0.01
Discontinued operations (in dollars per share)	$ (0.04)	$ (0.02)
Net income (loss) attributable to common stockholders (in dollars per share)	$ 0.04	$ (0.01)
Diluted Earnings (Loss) Per Common Share
Income (loss) from continuing operations (in dollars per share)	$ 0.08	$ 0.01
Discontinued operations (in dollars per share)	$ (0.04)	$ (0.02)
Net income (loss) attributable to common stockholders (in dollars per share)	$ 0.04	$ (0.01)