Earnings Per Share (EPS) - Schedule of Diluted Earnings Per Shares Calculation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Calculation of net income per share:
Net income	$ 13,150	$ 9,626	$ 27,060	$ 16,209
Basic weighted average shares outstanding (in shares)	49,848	49,547	49,812	49,511
Basic income per share (in dollars per share)	$ 0.26	$ 0.19	$ 0.54	$ 0.33
Effect of stock options outstanding:
Basic weighted average shares outstanding (in shares)	49,848	49,547	49,812	49,511
Effect from dilutive shares and options outstanding (in shares)	294	523	306	518
Diluted weighted average shares (in shares)	50,142	50,070	50,118	50,029
Diluted income per share (in dollars per share)	$ 0.26	$ 0.19	$ 0.54	$ 0.32