Stockholders' Equity (Details 2) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Weighted average Common Shares outstanding
Weighted average Common Shares outstanding	90,988,589	77,977,278	89,859,083	77,961,391
Nonvested shares	(1,784,422)	(1,515,012)	(1,803,451)	(1,516,904)
Weighted average Common Shares—Basic	89,204,167	76,462,266	88,055,632	76,444,487
Dilutive effect of restricted stock	0	1,127,522	0	1,108,456
Dilutive effect of employee stock purchase plan	0	122,705	0	125,419
Weighted average Common Shares outstanding—Diluted	89,204,167	77,712,493	88,055,632	77,678,362
Net Income (Loss)
Income (loss) from continuing operations	$ (26,522)	$ 2,220	$ (24,461)	$ 3,654
Noncontrolling interests’ share in net (income) loss	33	(20)	52	(20)
Income (loss) from continuing operations attributable to common stockholders	(26,489)	2,200	(24,409)	3,634
Discontinued operations	2,284	708	(795)	2,408
NET INCOME (LOSS) ATTRIBUTABLE TO COMMON STOCKHOLDERS	$ (24,205)	$ 2,908	$ (25,204)	$ 6,042
Basic Earnings (Loss) Per Common Share
Income (loss) from continuing operations (in dollars per share)	$ (0.30)	$ 0.03	$ (0.28)	$ 0.05
Discontinued operations (in dollars per share)	$ 0.03	$ 0.01	$ (0.01)	$ 0.03
Net income (loss) attributable to common stockholders (in dollars per share)	$ (0.27)	$ 0.04	$ (0.29)	$ 0.08
Diluted Earnings (Loss) Per Common Share
Income (loss) from continuing operations (in dollars per share)	$ (0.30)	$ 0.03	$ (0.28)	$ 0.05
Discontinued operations (in dollars per share)	$ 0.03	$ 0.01	$ (0.01)	$ 0.03
Net income (loss) attributable to common stockholders (in dollars per share)	$ (0.27)	$ 0.04	$ (0.29)	$ 0.08