Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash dividends declared	$ 2.34	$ 2.29	$ 2.20
Total Shareholders’ Equity	$ 681,105	$ 701,106	$ 657,983
Cash dividends declared	$ 2.34	$ 2.29	$ 2.20
Exercise of stock options	14,603	4,921	11,721
Purchase of treasury shares	760,000	573,000	261,000
Retained Earnings [Member]
Total Shareholders’ Equity	$ 641,826	$ 589,988	$ 539,253
Common Stock [Member]
Total Shareholders’ Equity	47,619	47,619	47,619
Capital Surplus[Member]
Total Shareholders’ Equity	170,942	171,304	170,309
Treasury Stock, Common [Member]
Total Shareholders’ Equity	(193,542)	(139,038)	(105,038)
Accumulated Other Comprehensive Income (Loss) [Member]
Total Shareholders’ Equity	$ 14,260	$ 31,233	$ 5,840