Consolidated Statement of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]
Balance at Dec. 31, 2019	$ 120,717	$ 2,303	$ 21,261	$ 99,372	$ 257	$ (2,476)
Balance (in shares) at Dec. 31, 2019		3,519,767
Net income	4,154			4,154
Other comprehensive income (loss), net of tax	5,462				5,462
Cash dividends declared	(2,399)			(2,399)
Stock issued in connection with dividend reinvestment and stock purchase plan	460	$ 10	450
Stock issued in connection with dividend reinvestment and stock purchase plan (in shares)		16,450
Stock issued for employee stock purchase plan	75	$ 2	73
Stock issued for employee stock purchase plan (in shares)		2,923
Stock issued for options exercised	$ 37	$ 2	35
Stock issued for options exercised (in shares)	9,550	3,121
Stock-based compensation expense	$ 57		57
Balance at Jun. 30, 2020	128,563	$ 2,317	21,876	101,127	5,719	(2,476)
Balance (in shares) at Jun. 30, 2020		3,542,261
Balance at Mar. 31, 2020	124,613	$ 2,309	21,537	98,395	4,848	(2,476)
Balance (in shares) at Mar. 31, 2020		3,530,670
Net income	3,934			3,934
Other comprehensive income (loss), net of tax	871				871
Cash dividends declared	(1,202)			(1,202)
Stock issued in connection with dividend reinvestment and stock purchase plan	240	$ 6	234
Stock issued in connection with dividend reinvestment and stock purchase plan (in shares)		8,668
Stock issued for employee stock purchase plan	75	$ 2	73
Stock issued for employee stock purchase plan (in shares)		2,923
Stock-based compensation expense	32		32
Balance at Jun. 30, 2020	128,563	$ 2,317	21,876	101,127	5,719	(2,476)
Balance (in shares) at Jun. 30, 2020		3,542,261
Balance at Dec. 31, 2020	$ 134,445	$ 2,328	22,430	106,644	5,649	(2,606)
Balance (in shares) at Dec. 31, 2020	3,556,533	3,556,533
Net income	$ 8,919			8,919
Other comprehensive income (loss), net of tax	(3,648)				(3,648)
Cash dividends declared	(2,489)			(2,489)
Stock issued in connection with dividend reinvestment and stock purchase plan	421	$ 8	413
Stock issued in connection with dividend reinvestment and stock purchase plan (in shares)		12,143
Stock issued for employee stock purchase plan	75	$ 2	73
Stock issued for employee stock purchase plan (in shares)		2,744
Stock issued for options exercised	$ 187	$ 4	183
Stock issued for options exercised (in shares)	19,025	6,517
Stock-based compensation expense	$ 63		63
Treasury stock purchase	(633)					(633)
Treasury stock purchase (in shares)		(18,391)
Balance at Jun. 30, 2021	$ 137,340	$ 2,342	23,162	113,074	2,001	(3,239)
Balance (in shares) at Jun. 30, 2021	3,559,546	3,559,546
Balance at Mar. 31, 2021	$ 131,996	$ 2,335	22,781	110,451	(678)	(2,893)
Balance (in shares) at Mar. 31, 2021		3,559,169
Net income	3,869			3,869
Other comprehensive income (loss), net of tax	2,679				2,679
Cash dividends declared	(1,246)			(1,246)
Stock issued in connection with dividend reinvestment and stock purchase plan	214	$ 4	210
Stock issued in connection with dividend reinvestment and stock purchase plan (in shares)		5,824
Stock issued for employee stock purchase plan	75	$ 2	73
Stock issued for employee stock purchase plan (in shares)		2,744
Stock issued for options exercised	56	$ 1	55
Stock issued for options exercised (in shares)		1,500
Stock-based compensation expense	43		43
Treasury stock purchase	(346)					(346)
Treasury stock purchase (in shares)		(9,691)
Balance at Jun. 30, 2021	$ 137,340	$ 2,342	$ 23,162	$ 113,074	$ 2,001	$ (3,239)
Balance (in shares) at Jun. 30, 2021	3,559,546	3,559,546