Net Income Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Net income	$ 4,856	$ 6,412	$ 9,949	$ 9,269	$ 9,745	$ 8,211	$ 21,217	$ 27,225
Basic weighted-average common shares outstanding (in shares)	39,123			38,342			38,901	38,155
Effect of dilutive stock options (in shares)	85			31			82	70
Effect of dilutive restricted stock (in shares)	1,078			1,029			1,140	1,242
Diluted weighted-average common shares outstanding (in shares)	40,286			39,402			40,123	39,467
Basic income per common share (in dollars per share)	$ 0.12			$ 0.24			$ 0.55	$ 0.71
Diluted income per common share (in dollars per share)	$ 0.12			$ 0.24			$ 0.53	$ 0.69
Antidilutive securities excluded from diluted net income per common share (in shares)	48			355			44	346