Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Capital Stock [Member]	Surplus [Member]	Undivided Profits [Member]	Accumulated Other Comprehensive Income [Member]	Treasury Stock [Member]	Total	Cumulative Effect, Period of Adoption, Adjustment [Member] Capital Stock [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Surplus [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Undivided Profits [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Accumulated Other Comprehensive Income [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Treasury Stock [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at Dec. 31, 2021	$ 20,046	$ 256,661	$ 349,056	$ 12,147	$ (36,782)	$ 601,128
Balance (ASU 2016-13 [Member]) at Dec. 31, 2021	20,046	256,661	345,586	12,147	(36,782)	597,658	$ 0	$ 0	$ (3,470)	$ 0	$ 0	$ (3,470)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	17,089	0	0	17,089
Other comprehensive income (loss), net of tax	0	0	0	(14,516)	0	(14,516)
Cash dividend declared	0	0	(6,727)	0	0	(6,727)
Purchase of treasury stock	0	0	0	0	(609)	(609)
Balance at Mar. 31, 2022	20,046	256,661	355,948	(2,369)	(37,391)	592,895
Balance at Dec. 31, 2022	20,058	257,078	393,831	(27,194)	(43,786)	599,987
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	17,746	0	0	17,746
Other comprehensive income (loss), net of tax	0	0	0	3,819	0	3,819
Cash dividend declared	0	0	(6,849)	0	0	(6,849)
Balance at Mar. 31, 2023	$ 20,058	$ 257,078	$ 404,728	$ (23,375)	$ (43,786)	$ 614,703