CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common stock amount	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock	Total
Balance at beginning of period (Accounting Standards Update 2016-13) at Dec. 31, 2020			$ (5,242)			$ (5,242)
Balance at beginning of period at Dec. 31, 2020	$ 32,857	$ 190,084	195,607	$ 6,740	$ (18,223)	407,065
Increase (Decrease) in Stockholders' Equity
Net income			18,505			18,505
Other comprehensive loss				(858)		(858)
Cash dividends declared			(6,876)			(6,876)
Net issuance to employee stock plans, including related tax effects		(280)			449	169
Recognition of stock based compensation		997				997
Balance at end of period at Jun. 30, 2021	32,857	190,801	201,994	5,882	(17,774)	413,760
Balance at beginning of period (Accounting Standards Update 2016-13) at Dec. 31, 2020			(5,242)			(5,242)
Balance at beginning of period at Dec. 31, 2020	32,857	190,084	195,607	6,740	(18,223)	407,065
Increase (Decrease) in Stockholders' Equity
Net income						29,533
Other comprehensive loss				(3,852)		(3,852)
Balance at end of period at Sep. 30, 2021	32,857	190,892	209,426	2,888	(17,628)	418,435
Balance at beginning of period at Jun. 30, 2021	32,857	190,801	201,994	5,882	(17,774)	413,760
Increase (Decrease) in Stockholders' Equity
Net income			11,028			11,028
Other comprehensive loss				(2,994)		(2,994)
Cash dividends declared			(3,596)			(3,596)
Net issuance to employee stock plans, including related tax effects		(276)			146	(130)
Recognition of stock based compensation		367				367
Balance at end of period at Sep. 30, 2021	32,857	190,892	209,426	2,888	(17,628)	418,435
Balance at beginning of period at Dec. 31, 2021	32,857	190,876	215,592	2,303	(17,481)	424,147
Increase (Decrease) in Stockholders' Equity
Net income			19,615			19,615
Other comprehensive loss				(43,274)		(43,274)
Cash dividends declared			(7,509)			(7,509)
Net issuance to employee stock plans, including related tax effects		376			148	524
Recognition of stock based compensation		94				94
Balance at end of period at Jun. 30, 2022	32,857	191,346	227,698	(40,971)	(17,333)	393,597
Balance at beginning of period at Dec. 31, 2021	32,857	190,876	215,592	2,303	(17,481)	424,147
Increase (Decrease) in Stockholders' Equity
Net income						31,045
Other comprehensive loss				(64,892)		(64,892)
Balance at end of period at Sep. 30, 2022	32,857	191,438	235,218	(62,589)	(16,959)	379,965
Balance at beginning of period at Jun. 30, 2022	32,857	191,346	227,698	(40,971)	(17,333)	393,597
Increase (Decrease) in Stockholders' Equity
Net income			11,430			11,430
Other comprehensive loss				(21,618)		(21,618)
Cash dividends declared			(3,910)			(3,910)
Net issuance to employee stock plans, including related tax effects		(530)			374	(156)
Recognition of stock based compensation		622				622
Balance at end of period at Sep. 30, 2022	$ 32,857	$ 191,438	$ 235,218	$ (62,589)	$ (16,959)	$ 379,965