Consolidated Statements of Changes in Shareholders' Equity - USD ($)	Total	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Accumulated Other Comprehensive (Loss) Income [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Treasury Stock [Member]
Beginning balance at Dec. 31, 2019	$ 675,122,000		$ 157,784,000	$ 294,999,000	$ 288,803,000		$ (21,730,000)		$ (44,734,000)
Beginning balance (Accounting Standards Update 2016-13) at Dec. 31, 2019		$ (11,047,000)				$ (11,284,000)		$ 237,000
Beginning balance, shares at Dec. 31, 2019			29,334,629
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	46,916,000				46,916,000
Other comprehensive income (loss), net of income tax (benefit)	(651,000)						(651,000)
Cash dividends declared	(17,522,000)				(17,522,000)
Stock-based compensation	1,353,000			1,367,000	(14,000)
Stock issued under dividend reinvestment and employee stock purchase plans	2,369,000			(197,000)					2,566,000
Stock issued under dividend reinvestment and employee stock purchase plans, shares			140,721
Vesting of restricted stock unit awards	(70,000)			(346,000)					276,000
Vesting of restricted stock unit awards, shares			13,175
Exercise of stock options	384,000			(55,000)					439,000
Exercise of stock options, shares			21,500
Cancellations of performance-based restricted stock awards				418,000					(418,000)
Cancellations of performance-based restricted stock awards, shares			(14,777)
Purchases of treasury stock	(4,382,000)								(4,382,000)
Purchases of treasury stock, shares			(200,196)
Ending balance at Dec. 31, 2020	$ 692,472,000		$ 157,784,000	296,186,000	306,899,000		(22,144,000)		(46,253,000)
Ending balance, shares at Dec. 31, 2020			29,295,052
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends declared, per share	$ 0.60
Net income	$ 91,801,000				91,801,000
Other comprehensive income (loss), net of income tax (benefit)	5,791,000						5,791,000
Cash dividends declared	(23,519,000)				(23,519,000)
Stock-based compensation	3,457,000			3,513,000	(56,000)
Stock issued under dividend reinvestment and employee stock purchase plans	2,384,000			153,000	(1,000)				2,232,000
Stock issued under dividend reinvestment and employee stock purchase plans, shares			86,187
Vesting of restricted stock unit awards	(355,000)			(1,153,000)					798,000
Vesting of restricted stock unit awards, shares			43,963
Exercise of stock options	2,058,000			155,000					1,903,000
Exercise of stock options, shares			93,033
Cancellations of performance-based restricted stock awards				327,000					(327,000)
Cancellations of performance-based restricted stock awards, shares			(7,199)
Purchases of treasury stock	(295,000)								(295,000)
Purchases of treasury stock, shares			(10,494)
Ending balance at Dec. 31, 2021	$ 773,794,000		$ 157,784,000	299,181,000	375,124,000		(16,353,000)		(41,942,000)
Ending balance, shares at Dec. 31, 2021			29,500,542
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends declared, per share	$ 0.80
Net income	$ 78,120,000				78,120,000
Other comprehensive income (loss), net of income tax (benefit)	(45,751,000)						(45,751,000)
Cash dividends declared	(24,399,000)				(24,399,000)
Stock-based compensation	3,781,000			3,989,000	(208,000)
Stock issued under dividend reinvestment and employee stock purchase plans	2,541,000			169,000	0				2,372,000
Stock issued under dividend reinvestment and employee stock purchase plans, shares			96,366
Vesting of restricted stock unit awards	(903,000)			(2,551,000)					1,648,000
Vesting of restricted stock unit awards, shares			92,073
Exercise of stock options	$ 698,000			20,000					678,000
Exercise of stock options, shares	32,934		32,934
Purchases of treasury stock	$ (11,381,000)								(11,381,000)
Purchases of treasury stock, shares			(450,000)
Ending balance at Dec. 31, 2022	$ 776,500,000		$ 157,784,000	$ 300,808,000	$ 428,637,000		$ (62,104,000)		$ (48,625,000)
Ending balance, shares at Dec. 31, 2022			29,271,915
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends declared, per share	$ 0.83