CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Total
Balance at Dec. 31, 2016	$ 79,114	$ 977	$ 14,557	$ (2,350)	$ 92,298
Balance (in shares) at Dec. 31, 2016	11,148,446
Net income					2,513
Other comprehensive loss, net of tax					(26)
Balance at Mar. 31, 2017				(2,376)
Balance at Dec. 31, 2016	$ 79,114	977	14,557	(2,350)	92,298
Balance (in shares) at Dec. 31, 2016	11,148,446
Net income			8,748		8,748
Other comprehensive loss, net of tax				(1,448)	(1,448)
Stock dividend adjustment	$ 207		(207)		0
Stock dividend adjustment (in shares)	289
Tax rate change reclassification			599	(599)	0
4% stock dividend declared in 2018	$ 5,806		(5,806)		0
4% stock dividend declared in 2018 (in shares)	447,312
Cash in lieu of fractional shares			(10)		(10)
Cash in lieu of fractional shares (in shares)	(129)
Stock-based compensation	$ 378				378
Common shares issued related to restricted stock grants, net of restricted stock reversals	$ 78				78
Common shares issued related to restricted stock grants, net of restricted stock reversals (in shares)	34,211
Balance at Dec. 31, 2017	$ 85,583	977	17,881	(4,397)	100,044
Balance (in shares) at Dec. 31, 2017	11,630,129
Net income			2,733		2,733
Other comprehensive loss, net of tax				(1,811)	(1,811)
Stock dividend adjustment	$ 240		(240)		0
Stock dividend adjustment (in shares)	628
Cash in lieu of fractional shares			(10)		(10)
Cash in lieu of fractional shares (in shares)	(159)
Stock-based compensation	$ 108				108
Common shares issued related to restricted stock grants, net of restricted stock reversals	$ 0				0
Common shares issued related to restricted stock grants, net of restricted stock reversals (in shares)	25,281
Stock options exercised, net	$ 0				0
Stock options exercised, net (in shares)	5,978
Balance at Mar. 31, 2018	$ 85,931	$ 977	$ 20,364	$ (6,208)	$ 101,064
Balance (in shares) at Mar. 31, 2018	11,661,857