Earnings Per Share (EPS) - Schedule of Diluted Earnings Per Shares Calculation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Calculation of net income per share:
Net income	$ 14,354	$ 15,534	$ 41,414	$ 31,743
Basic weighted average shares outstanding (in shares)	49,857	49,559	49,827	49,527
Basic income per share (in dollars per share)	$ 0.29	$ 0.31	$ 0.83	$ 0.64
Effect of stock options outstanding:
Basic weighted average shares outstanding (in shares)	49,857	49,559	49,827	49,527
Effect from dilutive shares and options outstanding (in shares)	272	558	283	517
Diluted weighted average shares (in shares)	50,129	50,117	50,110	50,044
Diluted income per share (in dollars per share)	$ 0.29	$ 0.31	$ 0.83	$ 0.63