Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Revision of Prior Period, Accounting Standards Update, Adjustment	Previously Reported	Common Stock	Common Stock Previously Reported	Capital Surplus	Capital Surplus Previously Reported	Retained Earnings	Retained Earnings Revision of Prior Period, Accounting Standards Update, Adjustment	Retained Earnings Previously Reported	Treasury Stock	Treasury Stock Previously Reported	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Previously Reported
Beginning Balance at Dec. 31, 2021	$ 681,105			$ 47,619		$ 170,942		$ 641,826			$ (193,542)		$ 14,260
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	44,025							44,025
Other comprehensive income (loss)	(98,243)												(98,243)
Cash dividends declared	(17,918)							(17,918)
Stock-based compensation expense	1,658					1,658
Restricted awards granted	0					(2,658)					2,658
Purchase of treasury shares	(19,295)										(19,295)
Ending balance at Jun. 30, 2022	591,993			47,619		169,557		667,933			(209,133)		(83,983)
Beginning Balance at Mar. 31, 2022	632,430			47,619		170,206		654,138			(194,819)		(44,714)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	22,683							22,683
Other comprehensive income (loss)	(39,269)												(39,269)
Cash dividends declared	(8,888)							(8,888)
Stock-based compensation expense	687					687
Restricted awards granted	0					(951)					951
Exercise of stock options	661					(385)					1,046
Purchase of treasury shares	(16,311)										(16,311)
Ending balance at Jun. 30, 2022	591,993			47,619		169,557		667,933			(209,133)		(83,983)
Beginning Balance at Dec. 31, 2022	578,027	$ 175	$ 577,852	47,619	$ 47,619	170,980	$ 170,980	706,871	$ 175	$ 706,696	(215,955)	$ (215,955)	(131,488)	$ (131,488)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	57,074							57,074
Other comprehensive income (loss)	1,040												1,040
Cash dividends declared	(19,697)							(19,697)
Stock-based compensation expense	1,726					1,726
Restricted awards granted	0					(3,534)					3,534
Purchase of treasury shares	(44,056)										(44,056)
Acquisition of Citizens Commerce Bancshares, Inc.	62,078					7,574					54,504
Ending balance at Jun. 30, 2023	636,192			47,619		176,746		744,248			(201,973)		(130,448)
Beginning Balance at Mar. 31, 2023	651,050			47,619		177,529		721,727			(179,436)		(116,389)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	32,733							32,733
Other comprehensive income (loss)	(14,059)												(14,059)
Cash dividends declared	(10,212)							(10,212)
Stock-based compensation expense	633					633
Restricted awards granted	0					(1,416)					1,416
Purchase of treasury shares	(23,953)										(23,953)
Ending balance at Jun. 30, 2023	$ 636,192			$ 47,619		$ 176,746		$ 744,248			$ (201,973)		$ (130,448)