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, 2018	$ 5,134	$ 24,821	$ 42,525	$ (4,299)	$ (803)	$ 67,378
Beginning balance, shares at Dec. 31, 2018	5,092,048
Net income			3,258			3,258
Other comprehensive income				3,998		3,998
Reclassification for ASU			83	(83)
Cash dividends at $0.22 per share			(2,244)			(2,244)
Stock-based compensation		(47)				(47)
Forfeiture of restricted stock, Shares	(800)
Treasury stock issued for stock plans		(2)			91	89
Treasury stock issued for stock plans, shares	4,880
Common stock issued for stock plans	$ 8	(8)
Common stock issued for stock plans, shares	7,500
Ending balance at Jun. 30, 2019	$ 5,142	24,858	43,622	(384)	(712)	72,526
Ending balance, shares at Jun. 30, 2019	5,103,628
Beginning balance at Dec. 31, 2018	$ 5,134	24,821	42,525	(4,299)	(803)	67,378
Beginning balance, shares at Dec. 31, 2018	5,092,048
Other comprehensive income				4,898
Ending balance at Dec. 31, 2019	$ 5,142	24,898	43,954	516	(803)	$ 73,707
Ending balance, shares at Dec. 31, 2019	5,099,729					5,099,729
Beginning balance at Mar. 31, 2019	$ 5,142	24,832	42,901	(2,899)	(803)	$ 69,173
Beginning balance, shares at Mar. 31, 2019	5,098,748
Net income			1,845			1,845
Other comprehensive income				2,515		2,515
Cash dividends at $0.22 per share			(1,124)			(1,124)
Stock-based compensation		28				28
Treasury stock issued for stock plans		(2)			91	89
Treasury stock issued for stock plans, shares	4,880
Ending balance at Jun. 30, 2019	$ 5,142	24,858	43,622	(384)	(712)	72,526
Ending balance, shares at Jun. 30, 2019	5,103,628
Beginning balance at Dec. 31, 2019	$ 5,142	24,898	43,954	516	(803)	$ 73,707
Beginning balance, shares at Dec. 31, 2019	5,099,729					5,099,729
Net income			2,643			$ 2,643
Other comprehensive income				3,040		3,040
Cash dividends at $0.22 per share			(2,242)			(2,242)
Stock-based compensation		(63)				(63)
Purchase of treasury stock					(379)	(379)
Purchase of treasury stock, shares	(27,000)
Treasury stock issued for stock plans		(6)			76	70
Treasury stock issued for stock plans, shares	4,459
Common stock issued for stock plans	$ 9	(9)
Common stock issued for stock plans, shares	9,530
Ending balance at Jun. 30, 2020	$ 5,151	24,946	44,355	3,556	(1,106)	$ 76,902
Ending balance, shares at Jun. 30, 2020	5,086,718					5,086,718
Beginning balance at Mar. 31, 2020	$ 5,151	24,918	43,870	4,416	(989)	$ 77,366
Beginning balance, shares at Mar. 31, 2020	5,093,859
Net income			1,605			1,605
Other comprehensive income				(860)		(860)
Cash dividends at $0.22 per share			(1,120)			(1,120)
Stock-based compensation		34				34
Purchase of treasury stock					(193)	(193)
Purchase of treasury stock, shares	(11,600)
Treasury stock issued for stock plans		(6)			76	70
Treasury stock issued for stock plans, shares	4,459
Ending balance at Jun. 30, 2020	$ 5,151	$ 24,946	$ 44,355	$ 3,556	$ (1,106)	$ 76,902
Ending balance, shares at Jun. 30, 2020	5,086,718					5,086,718