EPS (Computation of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net income	$ 19,740	$ 13,493
Dividends and undistributed earnings allocated to participating securities	(53)	(28)
Net income available to common shareholders	$ 19,687	$ 13,465
Weighted-average common shares outstanding for basic EPS	14,916,387	15,103,176
Dilutive effect of stock-based awards (shares)	78,147	44,042
Weighted-average common and potential common shares for diluted EPS (shares)	14,994,534	15,147,218
Basic EPS (in dollars per share)	$ 1.32	$ 0.89
Diluted EPS (in dollars per share)	$ 1.31	$ 0.89