Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjusted Balance	Common Stock	Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Capital Surplus	Capital Surplus Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings Cumulative Effect, Period of Adoption, Adjusted Balance	Treasury Stock	Treasury Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Cumulative Effect, Period of Adoption, Adjusted Balance
Beginning Balance at Dec. 31, 2022	$ 577,852	$ 175	$ 578,027	$ 47,619	$ 47,619	$ 170,980	$ 170,980	$ 706,696	$ 175	$ 706,871	$ (215,955)	$ (215,955)	$ (131,488)	$ (131,488)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	24,341			0		0		24,341			0		0
Other comprehensive income (loss)	15,099			0		0		0			0		15,099
Cash dividends declared	(9,485)			0		0		(9,485)			0		0
Stock-based compensation expense	1,093			0		1,093		0			0		0
Restricted awards granted	0			0		(2,118)		0			2,118		0
Purchase of treasury shares	(20,103)			0		0		0			(20,103)		0
Acquisition of Citizens Commerce Bancshares, Inc.	62,078			0		7,574		0			54,504		0
Ending balance at Mar. 31, 2023	651,050			47,619		177,529		721,727			(179,436)		(116,389)
Beginning Balance at Dec. 31, 2022	$ 577,852	$ 175	$ 578,027	47,619	$ 47,619	170,980	$ 170,980	706,696	$ 175	$ 706,871	(215,955)	$ (215,955)	(131,488)	$ (131,488)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible List]	Accounting Standards Update 2022-02 [Member]
Ending balance at Dec. 31, 2023	$ 677,066			47,619		177,424		780,299			(217,737)		(110,539)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	29,523			0		0		29,523			0		0
Other comprehensive income (loss)	(11,065)			0		0		0			0		(11,065)
Cash dividends declared	(10,798)			0		0		(10,798)			0		0
Stock-based compensation expense	1,100			0		(1,609)		0			2,709		0
Restricted awards granted	0			0		(9)		0			9		0
Exercise of stock options	58			0		(59)		0			117		0
Purchase of treasury shares	(3,653)			0		0		0			(3,653)		0
Ending balance at Mar. 31, 2024	$ 682,231			$ 47,619		$ 175,747		$ 799,024			$ (218,555)		$ (121,604)