Condensed Consolidated Statements of Changes in Shareholders' Equity - USD ($)	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Total
Treasury stock				$ (14,369,000)
Treasury Stock, shares				(845,988)
Beginning balance at Dec. 31, 2020	$ 255,000	$ 339,334,000	$ 214,456,000		$ 6,775,000	$ 546,451,000
Beginning balance, shares at Dec. 31, 2020	25,458,816
Net income			36,143,000			36,143,000
Dividends on common stock			(9,587,000)			(9,587,000)
Stock-based compensation expense		1,813,000				1,813,000
Vesting of restricted stock, net of shares withheld for employee tax liabilities		(87,000)				(87,000)
Vesting of restricted stock, net of shares withheld for employee tax liabilities, shares	18,997
Shares repurchased	$ (2,000)	(5,823,000)				(5,825,000)
Shares repurchased, shares	(214,219)
Other comprehensive income (loss), net of tax					(4,339,000)	(4,339,000)
Exercise of stock options, net of shares withheld for employee tax liabilities		(11,000)		$ 35,000		$ 24,000
Exercise of stock options, net of shares withheld for employee tax liabilities, shares				2,032
Retired treasury shares						214,219
Ending balance at Sep. 30, 2021	$ 253,000	335,226,000	241,012,000		2,436,000	$ 564,593,000
Ending balance, shares at Sep. 30, 2021	25,263,594
Treasury stock				$ (14,369,000)
Treasury Stock, shares				(845,988)
Beginning balance at Jun. 30, 2021	$ 253,000	335,399,000	229,785,000		5,159,000	556,227,000
Beginning balance, shares at Jun. 30, 2021	25,296,385
Net income			14,421,000			14,421,000
Dividends on common stock			(3,194,000)			(3,194,000)
Stock-based compensation expense		698,000				698,000
Vesting of restricted stock, net of shares withheld for employee tax liabilities		(3,000)				(3,000)
Vesting of restricted stock, net of shares withheld for employee tax liabilities, shares	339
Shares repurchased		(857,000)				(857,000)
Shares repurchased, shares	(33,130)
Other comprehensive income (loss), net of tax					(2,723,000)	(2,723,000)
Exercise of stock options, net of shares withheld for employee tax liabilities		(11,000)		$ 35,000		24,000
Exercise of stock options, net of shares withheld for employee tax liabilities, shares				2,032
Ending balance at Sep. 30, 2021	$ 253,000	335,226,000	241,012,000		2,436,000	564,593,000
Ending balance, shares at Sep. 30, 2021	25,263,594
Treasury stock				$ (14,334,000)
Treasury Stock, shares				(843,956)
Treasury stock				$ (14,196,000)		(14,196,000)
Treasury Stock, shares				(835,828)
Beginning balance at Dec. 31, 2021	$ 253,000	335,846,000	237,165,000		3,057,000	562,125,000
Beginning balance, shares at Dec. 31, 2021	25,323,558
Net income			35,049,000			35,049,000
Dividends on common stock			(9,410,000)			(9,410,000)
Stock-based compensation expense		1,537,000				1,537,000
Vesting of restricted stock, net of shares withheld for employee tax liabilities		(135,000)				(135,000)
Vesting of restricted stock, net of shares withheld for employee tax liabilities, shares	22,463
Shares repurchased	$ (5,000)	(15,036,000)				(15,041,000)
Shares repurchased, shares	(510,161)
Other comprehensive income (loss), net of tax					(72,873,000)	(72,873,000)
Exercise of stock options, net of shares withheld for employee tax liabilities	$ 6,407	23,000		$ 150,000		$ 173,000
Exercise of stock options, net of shares withheld for employee tax liabilities, shares				8,833
Retirement of Treasury Stock	$ (8,000)	(14,038,000)
Retired treasury shares	826,995					510,161
Retirement of treasury stock				$ 14,046,000
Retirement of treasury stock, shares				826,995
Ending balance at Sep. 30, 2022	$ 240,000	308,197,000	262,804,000		(69,816,000)	$ 501,425,000
Ending balance, shares at Sep. 30, 2022	24,015,272
Treasury stock				$ (14,046,000)
Treasury Stock, shares				(826,995)
Beginning balance at Jun. 30, 2022	$ 253,000	334,104,000	253,180,000		(46,812,000)	526,679,000
Beginning balance, shares at Jun. 30, 2022	25,252,256
Net income			12,747,000			12,747,000
Dividends on common stock			(3,123,000)			(3,123,000)
Stock-based compensation expense		515,000				515,000
Vesting of restricted stock, net of shares withheld for employee tax liabilities	$ 350	(4,000)				(4,000)
Shares repurchased	$ (5,000)	(12,453,000)				(12,458,000)
Shares repurchased, shares	(416,746)
Other comprehensive income (loss), net of tax					(23,004,000)	(23,004,000)
Exercise of stock options, net of shares withheld for employee tax liabilities		73,000				73,000
Exercise of stock options, net of shares withheld for employee tax liabilities, shares	6,407
Retirement of Treasury Stock	$ (8,000)	(14,038,000)				$ (14,000,000.0)
Retired treasury shares	826,995					826,995
Retirement of treasury stock				$ 14,046,000
Retirement of treasury stock, shares				826,995
Ending balance at Sep. 30, 2022	$ 240,000	$ 308,197,000	$ 262,804,000		$ (69,816,000)	$ 501,425,000
Ending balance, shares at Sep. 30, 2022	24,015,272
Treasury Stock, shares						(835,828)