Earnings Per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Net income	$ 14,697	$ 9,193	$ 29,827	$ 16,344
Basic earnings per share - weighted average shares outstanding	31,859	31,501	31,760	31,397
Employee stock options and restricted stock units - dilutive shares	578	645	617	704
Warrant - dilutive shares	0	0	0	3
Diluted earnings per share - weighted average shares outstanding	32,437	32,146	32,377	32,104
Basic	$ 0.46	$ 0.29	$ 0.94	$ 0.52
Diluted	$ 0.45	$ 0.29	$ 0.92	$ 0.51