Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended									12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Dec. 31, 2011	Dec. 31, 2010
Numerator:
Net income (loss) attributable to common shareholders	$ 3,456	$ 2,825	$ 1,753	$ (3,591)	$ (1,921)	$ (308)	$ (3,814)	$ (599)	$ (147)	$ 4,443	$ (6,642)
Less: Dividends paid on unvested share-based compensation										(398)	(9)
Net income (loss) available to common shareholders									$ (147)	$ 4,045	$ (6,651)
Denominator:
Weighted-average number of common shares-basic									4,011,198	47,921,200	28,669,851
Effect of dilutive share-based compensation										45,107
Weighted-average number of common shares-diluted									4,011,198	47,966,307	28,669,851
Net income (loss) per share available to common shareholders-basic									$ (0.04)	$ 0.08	$ (0.23)
Net income (loss) per share available to common shareholders-diluted									$ (0.04)	$ 0.08	$ (0.23)