Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock, Voting	Common Stock, Nonvoting	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning balance at Dec. 31, 2017	$ 146,946	$ 878	$ 11,450	$ 133	$ 118,120	$ 18,892	$ (2,527)
Beginning balance, shares at Dec. 31, 2017			11,449,465	132,561
Issuance of restricted common stock, net of forfeitures and withholdings to satisfy employee tax obligations	(329)		$ 25		(354)
Issuance of restricted common stock, net of forfeitures and withholdings to satisfy employee tax obligations, shares			24,729
Stock-based compensation expense	305				305
Exercise of employee common stock options, net of withholdings to satisfy employee tax obligations	300		$ 62		238
Exercise of employee common stock options, net of withholdings to satisfy employee tax obligations, shares			61,822
Exercise of common stock warrants	942		$ 104		838
Exercise of common stock warrants, shares			104,781
Net income	3,195					3,195
Other comprehensive loss	(2,666)						(2,666)
Ending balance at Mar. 31, 2018	148,693	878	$ 11,641	$ 133	119,147	22,087	(5,193)
Ending balance, shares at Mar. 31, 2018			11,640,797	132,561
Beginning balance at Dec. 31, 2018	254,379	878	$ 17,592	$ 133	211,789	27,303	(3,316)
Beginning balance, shares at Dec. 31, 2018			17,592,160	132,561
Issuance of restricted common stock, net of forfeitures and withholdings to satisfy employee tax obligations	(168)		$ 14		(182)
Issuance of restricted common stock, net of forfeitures and withholdings to satisfy employee tax obligations, shares			13,801
Stock-based compensation expense	344				344
Exercise of employee common stock options, net of withholdings to satisfy employee tax obligations	1,180		$ 182		998
Exercise of employee common stock options, net of withholdings to satisfy employee tax obligations, shares			182,002
Repurchase of commonstock	(2,431)		$ (155)		(2,276)
Repurchase of common, shares			(155,400)
Common and preferred stockdividends declared ($0.04per share)	(745)					(745)
Net income	4,780					4,780
Other comprehensive loss	2,412						2,412
Ending balance at Mar. 31, 2019	$ 259,751	$ 878	$ 17,633	$ 133	$ 210,673	$ 31,338	$ (904)
Ending balance, shares at Mar. 31, 2019			17,632,563	132,561