Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic EPS [Abstract]
Net income	$ 121,021	$ 112,566	$ 82,151
Weighted average shares, basic (in shares)	43,815	43,701	43,575
Basic EPS (in dollars per share)	$ 2.76	$ 2.58	$ 1.89
Diluted earnings per share [Abstract]
Net income	$ 121,021	$ 112,566	$ 82,151
Dilutive effect of stock based compensation (in shares)	309	319	330
Weighted average shares, diluted (in shares)	44,124	44,020	43,905
Diluted EPS (in dollars per share)	$ 2.74	$ 2.56	$ 1.87