Earnings per Common Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Numerator:
Net income (loss) attributable to common shareholders	$ (7,247)	$ (3,591)
Less: dividends paid on unvested share-based compensation	(83)	(15)
Undistributed earnings attributable to share-based compensation	0	0
Net income (loss) available to common shareholders	$ (7,330)	$ (3,606)
Denominator:
Weighted-average number of common shares-basic	51,009,904	39,827,551
Effect of dilutive share-based compensation	0	0
Weighted-average number of common shares-diluted	51,009,904	39,827,551
Net income (loss) per share attributable to common shareholders-basic	$ (0.14)	$ (0.09)
Net income (loss) per share attributable to common shareholders-diluted	$ (0.14)	$ (0.09)