CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common stock amount	Additional paid-in capital	Retained earnings impact of ASC 326	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock	impact of ASC 326	Total
Balance at beginning of period at Dec. 31, 2019	$ 32,857	$ 188,536		$ 175,780	$ 3,792	$ (4,677)		$ 396,288
Increase (Decrease) in Stockholders' Equity
Net income				33,244				33,244
Other comprehensive loss					2,948			2,948
Cash dividends declared				(13,417)				(13,417)
Treasury stock purchased						(14,188)		(14,188)
Net issuance to employee stock plans, including related tax effects		(22)				642		620
Recognition of stock based compensation		1,570						1,570
Balance at end of period at Dec. 31, 2020	32,857	190,084	$ (5,242)	195,607	6,740	(18,223)	$ (5,242)	407,065
Increase (Decrease) in Stockholders' Equity
Net income				39,299				39,299
Other comprehensive loss					(4,437)			(4,437)
Cash dividends declared				(14,072)				(14,072)
Net issuance to employee stock plans, including related tax effects		(1,357)				742		(615)
Recognition of stock based compensation		2,149						2,149
Balance at end 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				43,557				43,557
Other comprehensive loss					(60,643)			(60,643)
Cash dividends declared				(15,334)				(15,334)
Net issuance to employee stock plans, including related tax effects		(892)				677		(215)
Recognition of stock based compensation		1,938						1,938
Balance at end of period at Dec. 31, 2022	$ 32,857	$ 191,922		$ 243,815	$ (58,340)	$ (16,804)		$ 393,450