Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock [Member]	Total
Beginning balance at Dec. 31, 2020	$ 5,151	$ 25,011	$ 45,096	$ 3,518	$ (2,179)	$ 76,597
Beginning balance, shares at Dec. 31, 2020	5,025,441
Net income			1,635			1,635
Other comprehensive income (loss)				(4,108)		(4,108)
Cash dividends			(1,102)			(1,102)
Stock-based compensation		35				35
Purchase of treasury stock					(483)	(483)
Purchase of treasury stock, shares	(27,585)
Treasury stock issued for stock plans		(153)			153
Treasury stock issued for stock plans, shares	8,839
Ending balance at Mar. 31, 2021	$ 5,151	24,893	45,629	(590)	(2,509)	72,574
Ending balance, shares at Mar. 31, 2021	5,006,695
Beginning balance at Dec. 31, 2021	$ 5,151	25,008	47,298	(3,365)	(2,802)	$ 71,290
Beginning balance, shares at Dec. 31, 2021	4,988,542					4,988,542
Net income			2,115			$ 2,115
Other comprehensive income (loss)				(15,614)		(15,614)
Cash dividends			(1,100)			(1,100)
Stock-based compensation		37				37
Purchase of treasury stock					(3)	(3)
Purchase of treasury stock, shares	(170)
Treasury stock issued for stock plans		(181)			181
Treasury stock issued for stock plans, shares	10,486
Ending balance at Mar. 31, 2022	$ 5,151	$ 24,864	$ 48,313	$ (18,979)	$ (2,624)	$ 56,725
Ending balance, shares at Mar. 31, 2022	4,998,858					4,998,858