Earnings Per Share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Numerator:
Net income	$ 8,083	$ 8,640	$ 13,556	$ 29,619
Denominator:
Weighted-average shares outstanding (in shares)	21,290,759	20,745,245	21,193,825	19,658,199
Effect of dilutive securities (in shares)	237,787	98,358	233,573	98,212
Weighted-average diluted shares (in shares)	21,528,546	20,843,603	21,427,398	19,756,411
Basic earnings per share (in usd per share)	$ 0.38	$ 0.42	$ 0.64	$ 1.51
Diluted earnings per share (in usd per share)	$ 0.38	$ 0.41	$ 0.63	$ 1.50