Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Treasury Stock [Member]	Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Total
Balance at Dec. 31, 2017	$ 4,379	$ (1,429)	$ 69,110	$ 32,272	$ (2,390)	$ 101,942
Net income				7,682		7,682
Other comprehensive income (loss)					(1,116)	(1,116)
Restricted stock compensation expense	10		260			270
Exercise of stock options	8		(8)
Shares withheld for employee taxes on stock option exercise and share award vest	(4)		(262)			(266)
Cash dividends - common				(902)		(902)
Non-cash funding of 401(k)		159	145			304
Non-cash funding of deferred comp. plan		74	71			145
Adoption impact - ASU 2018-02				471	(471)
Balance at Sep. 30, 2018	4,393	(1,196)	69,316	39,523	(3,977)	108,059
Balance at Jun. 30, 2018	4,385	(1,276)	69,268	36,804	(3,848)	105,333
Net income				3,020		3,020
Other comprehensive income (loss)					(129)	(129)
Restricted stock compensation expense	2		64			66
Exercise of stock options	6		(6)
Shares withheld for employee taxes on stock option exercise and share award vest			(86)			(86)
Cash dividends - common				(301)		(301)
Non-cash funding of 401(k)		57	53			110
Non-cash funding of deferred comp. plan		23	23			46
Balance at Sep. 30, 2018	4,393	(1,196)	69,316	39,523	(3,977)	108,059
Balance at Dec. 31, 2018	4,391	(1,130)	69,333	42,223	(2,971)	111,846
Net income				8,044		8,044
Other comprehensive income (loss)					1,470	1,470
Restricted stock compensation expense	(9)		234			225
Taxes on exercise of stock options			(8)			(8)
Cash dividends - common				(910)		(910)
Non-cash funding of 401(k)		153	143			296
Non-cash funding of deferred comp. plan		74	76			150
Balance at Sep. 30, 2019	4,382	(903)	69,778	49,357	(1,501)	121,113
Balance at Jun. 30, 2019	4,382	(961)	69,613	46,791	(1,669)	118,156
Net income				2,870		2,870
Other comprehensive income (loss)					168	168
Restricted stock compensation expense			82			82
Taxes on exercise of stock options			(8)			(8)
Cash dividends - common				(304)		(304)
Non-cash funding of 401(k)		39	60			99
Non-cash funding of deferred comp. plan		19	31			50
Balance at Sep. 30, 2019	$ 4,382	$ (903)	$ 69,778	$ 49,357	$ (1,501)	$ 121,113