Condensed Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Treasury Stock [Member]
Beginning balance at Dec. 31, 2021	$ 773,794	$ 157,784	$ 299,181	$ 375,124	$ (16,353)	$ (41,942)
Beginning balance, shares at Dec. 31, 2021		29,500,542
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	20,317			20,317
Other comprehensive income, net of income tax	(15,556)				(15,556)
Cash dividends declared	(5,905)			(5,905)
Stock-based compensation	869		1,073	(204)		0
Stock issued under dividend reinvestment and employee stock purchase plans	(623)		(59)			(564)
Stock issued under dividend reinvestment and employee stock purchase plans, shares		21,843
Vesting of restricted stock units, net of shares withheld to cover taxes	(863)		(2,418)			1,555
Vesting of restricted stock unit awards, shares		88,259
Exercise of stock options	576		50			526
Shares under option, exercised		25,781
Ending balance at Mar. 31, 2022	$ 773,855	$ 157,784	297,945	389,332	(31,909)	(39,297)
Ending balance, shares at Mar. 31, 2022		29,636,425
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends declared, per share	$ 0.20
Beginning balance at Dec. 31, 2022	$ 776,500	$ 157,784	300,808	428,637	(62,104)	(48,625)
Beginning balance, shares at Dec. 31, 2022		29,271,915
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	21,034			21,034
Other comprehensive income, net of income tax	6,554				6,554
Cash dividends declared	(6,151)			(6,151)
Stock-based compensation	1,030		1,057	(27)
Stock issued under dividend reinvestment and employee stock purchase plans	(662)		(29)			(633)
Stock issued under dividend reinvestment and employee stock purchase plans, shares		25,344
Vesting of restricted stock units, net of shares withheld to cover taxes	(1,207)		(3,713)			2,506
Vesting of restricted stock unit awards, shares		126,270
Exercise of stock options	$ 74		(14)			88
Shares under option, exercised	4,167	4,167
Ending balance at Mar. 31, 2023	$ 798,496	$ 157,784	$ 298,167	$ 443,493	$ (55,550)	$ (45,398)
Ending balance, shares at Mar. 31, 2023		29,427,696
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends declared, per share	$ 0.21