Net (Loss) Income per Share of Common Stock (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Numerators for earnings per share —
Net (loss) income that is available to common shareholders	$ (10,143)	$ 15,406	$ (9,502)	$ 14,405
Denominator for basic earnings per share —
Weighted average shares outstanding	20,837,843	20,099,003	20,803,629	20,027,493
Effect of stock options and restricted stock units	0	627,566	0	642,300
Effect of warrants	0	134,877	0	142,577
Total effect of dilutive securities (1)	0	762,443	0	784,877
Denominator for diluted earnings per share —
Adjusted weighted average shares and assumed conversions	20,837,843	20,861,446	20,803,629	20,812,370
Basic (loss) earnings per share	$ (0.49)	$ 0.77	$ (0.46)	$ 0.72
Diluted (loss) earnings per share	$ (0.49)	$ 0.74	$ (0.46)	$ 0.69
Anti-dilutive employee stock options and restricted stock units not included in the earnings per share calculation	437,680		424,483