Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
Beginning balance at Dec. 31, 2017	$ 4,811	$ 18,565	$ 40,876	$ (4,034)	$ (831)	$ 59,387
Beginning balance, shares at Dec. 31, 2017	4,767,656
Net income			3,302			3,302
Other comprehensive income (loss)				(2,048)		(2,048)
Reclassification for ASU 2016-01			156	(156)
Cash dividends at per share			(2,170)			(2,170)
Stock-based compensation		39				39
Purchase of treasury stock					(40)	(40)
Purchase of treasury stock, shares	(1,928)
Treasury stock issued for stock plans		(7)			98	91
Treasury stock issued for stock plans, shares	5,170
Common stock issued for stock plans	$ 8	34				42
Common stock issued for stock plans, shares	7,354
Common stock issued for acquisition	$ 315	6,148				6,463
Common stock issued acquisition, shares	315,284
Ending balance at Jun. 30, 2018	$ 5,134	24,779	42,164	(6,238)	(773)	65,066
Ending balance, shares at Jun. 30, 2018	5,093,536
Beginning balance at Mar. 31, 2018	$ 4,816	18,575	41,310	(5,869)	(833)	57,999
Beginning balance, shares at Mar. 31, 2018	4,772,948
Net income			1,975			1,975
Other comprehensive income (loss)				(369)		(369)
Cash dividends at per share			(1,121)			(1,121)
Stock-based compensation		21				21
Treasury stock issued for stock plans		(4)			60	56
Treasury stock issued for stock plans, shares	3,170
Common stock issued for stock plans	$ 3	39				42
Common stock issued for stock plans, shares	2,134
Common stock issued for acquisition	$ 315	6,148				6,463
Common stock issued acquisition, shares	315,284
Ending balance at Jun. 30, 2018	$ 5,134	24,779	42,164	(6,238)	(773)	65,066
Ending balance, shares at Jun. 30, 2018	5,093,536
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					5,092,048
Ending balance at Mar. 31, 2019	$ 5,142	24,832	42,818	(2,816)	(803)	$ 69,173
Ending balance, shares at Mar. 31, 2019	5,098,748
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					5,092,048
Net income			3,258			$ 3,258
Other comprehensive income (loss)				3,998		3,998
Cash dividends at 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	43,539	(301)	(712)	$ 72,526
Ending balance, shares at Jun. 30, 2019	5,103,628					5,103,628
Beginning balance at Mar. 31, 2019	$ 5,142	24,832	42,818	(2,816)	(803)	$ 69,173
Beginning balance, shares at Mar. 31, 2019	5,098,748
Net income			1,845			1,845
Other comprehensive income (loss)				2,515		2,515
Cash dividends at 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	$ 43,539	$ (301)	$ (712)	$ 72,526
Ending balance, shares at Jun. 30, 2019	5,103,628					5,103,628