Consolidated Statements of Changes in Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Total
Beginning Balance at Dec. 31, 2016	$ 24,806	$ 16,427	$ 56,965	$ (4,208)	$ 93,990
Beginning Balance (in shares) at Dec. 31, 2016	4,961,258
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	0	2,103	0	2,103
Other comprehensive income (loss), net of tax	0	0	0	1,464	1,464
Issuance of common stock related to acquisition					0
Exercise of stock options	$ 124	373	0	0	497
Exercise of stock options (in shares)	24,806
Employee Stock Purchase Plan share issuance	$ 9	38	0	0	47
Employee Stock Purchase Plan share issuance (in shares)	1,687
Repurchase and retirement of common stock	$ (18)	(80)	0	0	(98)
Repurchase and retirement of common stock (in shares)	(3,600)
Cash dividends	$ 0	0	(1,095)	0	(1,095)
Ending Balance at Jun. 30, 2017	$ 24,921	16,758	57,973	(2,744)	96,908
Ending Balance (in shares) at Jun. 30, 2017	4,984,151
Beginning Balance at Mar. 31, 2017				(3,780)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income					1,161
Other comprehensive income (loss), net of tax					1,036
Ending Balance at Jun. 30, 2017	$ 24,921	16,758	57,973	(2,744)	96,908
Ending Balance (in shares) at Jun. 30, 2017	4,984,151
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification of the income tax effects of the Tax Cuts and Jobs Act from AOCI | ASU 2018-02 [Member]	$ 0	0	139	(139)	0
Reclassification of net unrealized gains on equity securities from AOCI per ASU 2016-01 | ASU 2016-01 [Member]	0	0	77	(77)	0
Beginning Balance at Dec. 31, 2017	$ 25,087	17,270	54,738	(707)	$ 96,388
Beginning Balance (in shares) at Dec. 31, 2017	5,017,458				5,019,703
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	0	1,934	0	$ 1,934
Other comprehensive income (loss), net of tax	0	0	0	(1,966)	(1,966)
Issuance of common stock related to acquisition	$ 750	3,207	0	0	3,957
Issuance of common stock related to acquisition (in shares)	149,625
Employee Stock Purchase Plan share issuance	$ 10	38	0	0	48
Employee Stock Purchase Plan share issuance (in shares)	1,940
Stock-based compensation expense	$ 0	53	0	0	53
Cash dividends	0	0	(1,121)	0	(1,121)
Ending Balance at Jun. 30, 2018	$ 25,847	20,568	55,767	(2,889)	$ 99,293
Ending Balance (in shares) at Jun. 30, 2018	5,169,023				5,181,106
Beginning Balance at Mar. 31, 2018				(2,737)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income					$ 992
Other comprehensive income (loss), net of tax					(152)
Ending Balance at Jun. 30, 2018	$ 25,847	$ 20,568	$ 55,767	$ (2,889)	$ 99,293
Ending Balance (in shares) at Jun. 30, 2018	5,169,023				5,181,106