Condensed Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Beginning balance, shares at Dec. 31, 2022		29,271,915
Beginning balance at Dec. 31, 2022	$ 776,500	$ 157,784	$ 300,808	$ 428,637	$ (62,104)	$ (48,625)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	37,834			37,834
Other comprehensive income, net of income tax	1,070				1,070
Cash dividends declared	(12,331)			(12,331)
Stock-based compensation	1,957		2,291	(334)
Stock issued under dividend reinvestment and employee stock purchase plans, shares		61,636
Stock issued under dividend reinvestment and employee stock purchase plans	1,309		(19)			1,328
Vesting of restricted stock unit awards, shares		131,363
Vesting of restricted stock units, net of shares withheld to cover taxes	(1,231)		(3,850)			2,619
Shares under option, exercised		6,210
Exercise of stock options	114		(18)			132
Ending balance, shares at Jun. 30, 2023		29,471,124
Ending balance at Jun. 30, 2023	805,222	$ 157,784	299,212	453,806	(61,034)	(44,546)
Beginning balance, shares at Mar. 31, 2023		29,427,696
Beginning balance at Mar. 31, 2023	798,496	$ 157,784	298,167	443,493	(55,550)	(45,398)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	16,800			16,800
Other comprehensive income, net of income tax	(5,484)				(5,484)
Cash dividends declared	(6,180)			(6,180)
Stock-based compensation	927		1,234	(307)
Stock issued under dividend reinvestment and employee stock purchase plans, shares		36,292
Stock issued under dividend reinvestment and employee stock purchase plans	647		(48)			695
Vesting of restricted stock unit awards, shares		5,093
Vesting of restricted stock units, net of shares withheld to cover taxes	(24)		(137)			113
Shares under option, exercised		2,043
Exercise of stock options	40		(4)			44
Ending balance, shares at Jun. 30, 2023		29,471,124
Ending balance at Jun. 30, 2023	805,222	$ 157,784	299,212	453,806	(61,034)	(44,546)
Beginning balance, shares at Dec. 31, 2023		29,511,721
Beginning balance at Dec. 31, 2023	839,208	$ 157,784	301,066	474,691	(50,646)	(43,687)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	38,412			38,412
Other comprehensive income, net of income tax	(3,478)				(3,478)
Cash dividends declared	(12,332)			(12,332)
Stock-based compensation	2,059		2,348	(289)
Stock issued under dividend reinvestment and employee stock purchase plans, shares		59,227
Stock issued under dividend reinvestment and employee stock purchase plans	1,268		12			1,256
Vesting of restricted stock unit awards, shares		107,377
Vesting of restricted stock units, net of shares withheld to cover taxes	$ (857)		(3,212)			2,355
Shares under option, exercised	19,788	19,788
Exercise of stock options	$ 373		(48)			421
Purchases of treasury stock, shares		(507,473)
Purchases of treasury stock	(10,516)					(10,516)
Ending balance, shares at Jun. 30, 2024		29,190,640
Ending balance at Jun. 30, 2024	854,137	$ 157,784	300,166	500,482	(54,124)	(50,171)
Beginning balance, shares at Mar. 31, 2024		29,337,919
Beginning balance at Mar. 31, 2024	843,669	$ 157,784	298,914	488,790	(54,740)	(47,079)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	18,107			18,107
Other comprehensive income, net of income tax	616				616
Cash dividends declared	(6,143)			(6,143)
Stock-based compensation	1,106		1,378	(272)
Stock issued under dividend reinvestment and employee stock purchase plans, shares		27,321
Stock issued under dividend reinvestment and employee stock purchase plans	620		17			603
Vesting of restricted stock unit awards, shares		4,208
Vesting of restricted stock units, net of shares withheld to cover taxes	(23)		(111)			88
Shares under option, exercised		12,000
Exercise of stock options	223		(32)			255
Purchases of treasury stock, shares		(190,808)
Purchases of treasury stock	(4,038)		0			(4,038)
Ending balance, shares at Jun. 30, 2024		29,190,640
Ending balance at Jun. 30, 2024	$ 854,137	$ 157,784	$ 300,166	$ 500,482	$ (54,124)	$ (50,171)