EPS (Computation of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Net income	$ 14,640	$ 16,775	$ 52,523	$ 41,208
Dividends and undistributed earnings allocated to participating securities	(40)	(47)	(145)	(101)
Net income available to common shareholders	$ 14,600	$ 16,728	$ 52,378	$ 41,107
Weighted-average common shares outstanding for basic EPS	14,931,056	14,961,465	14,930,387	15,008,004
Dilutive effect of stock-based awards (shares)	67,957	39,582	66,154	36,423
Weighted-average common and potential common shares for diluted EPS (shares)	14,999,013	15,001,047	14,996,541	15,044,427
Basic EPS (in dollars per share)	$ 0.98	$ 1.12	$ 3.51	$ 2.74
Diluted EPS (in dollars per share)	$ 0.97	$ 1.11	$ 3.49	$ 2.73