Earnings Per Common Share (Calculation of Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Earnings Per Share [Abstract]
Net income	$ 19,957	$ 17,460	$ 36,440	$ 37,931
Less dividends and undistributed earnings allocated to participating securities	(57)	(52)	(111)	(108)
Net income available to common shareholders	$ 19,900	$ 17,408	$ 36,329	$ 37,823
Weighted average common shares outstanding - basic	17,303,000	17,314,000	17,317,000	17,295,000
Dilutive effect of common stock equivalents	111,000	122,000	134,000	150,000
Weighted average common shares outstanding - diluted	17,414,000	17,436,000	17,451,000	17,445,000
Basic earnings per common share	$ 1.15	$ 1.01	$ 2.10	$ 2.19
Diluted earnings per common share	$ 1.14	$ 1.00	$ 2.08	$ 2.17
Antidilutive common stock equivalents	196,943	87,924	141,043	149,650