Earnings per Common Share (Calculation of Earnings per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Earnings Per Share [Abstract]
Net income	$ 11,161	$ 18,668	$ 35,229	$ 55,108
Less dividends and undistributed earnings allocated to participating securities	(21)	(53)	(69)	(164)
Net income available to common shareholders	$ 11,140	$ 18,615	$ 35,160	$ 54,944
Weighted average common shares outstanding - basic	17,019,000	17,174,000	17,034,000	17,269,000
Dilutive effect of common stock equivalents	22,000	124,000	29,000	120,000
Weighted average common shares outstanding - diluted	17,041,000	17,298,000	17,063,000	17,389,000
Basic earnings per common share	$ 0.65	$ 1.08	$ 2.06	$ 3.18
Diluted earnings per common share	$ 0.65	$ 1.08	$ 2.06	$ 3.16
Antidilutive common stock equivalents	468,524	137,886	452,472	140,777