Parent Only Financial Information Parent Only Statement of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash Flows from Operating Activities:
Net Income	$ 49,857	$ 40,827	$ 37,475
Shares Issued Under the Directors’ Stock Plan	376	125	258
Net Cash Provided By Operating Activities	68,206	42,314	43,944
Cash Flows from Financing Activities:
Shares Issued for Stock Option Exercises, net	1,505	748	1,792
Shares Issued Under the Employee Stock Purchase Plan	481	513	493
Shares Issued for Dividend Reinvestment Plans	1,836	1,808	1,777
Purchase of Treasury Stock	(2,662)	(1,578)	(2,469)
Cash Dividends Paid	(16,296)	(15,740)	(15,206)
Net Cash Provided By Financing Activities	283,101	455,773	134,269
Net Increase (Decrease) in Cash and Cash Equivalents	76,705	310,770	(14,018)
Cash and Cash Equivalents at Beginning of Year	380,991	70,221	84,239
Cash and Cash Equivalents at End of Year	457,696	380,991	70,221
Interest on Deposits and Borrowings	5,373	13,799	20,843
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Cash Flows from Operating Activities:
Net Income	49,857	40,827	37,475
Undistributed Net Income of Subsidiaries	(34,403)	(24,526)	(23,753)
Shares Issued Under the Directors’ Stock Plan	376	125	258
Changes in Other Assets and Other Liabilities	(462)	(3,606)	(1,236)
Net Cash Provided By Operating Activities	15,368	12,820	12,744
Cash Flows from Financing Activities:
Shares Issued for Stock Option Exercises, net	1,505	748	1,792
Shares Issued Under the Employee Stock Purchase Plan	481	513	493
Shares Issued for Dividend Reinvestment Plans	1,836	1,808	1,777
Purchase of Treasury Stock	(2,662)	(1,578)	(2,469)
Cash Dividends Paid	(16,296)	(15,740)	(15,206)
Net Cash Provided By Financing Activities	(15,136)	(14,249)	(13,613)
Net Increase (Decrease) in Cash and Cash Equivalents	232	(1,429)	(869)
Cash and Cash Equivalents at Beginning of Year	0	1,429	2,298
Cash and Cash Equivalents at End of Year	232	0	1,429
Interest on Deposits and Borrowings	$ 686	$ 746	$ 1,024