Selected Quarterly Financial Data (unaudited) (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Interest income	$ 16,146	$ 15,373	$ 15,020	$ 14,748	$ 15,047	$ 14,121	$ 13,649	$ 13,362	$ 61,287	$ 56,179
Interest expense	3,043	2,408	2,039	1,727	1,742	1,615	1,456	1,276	9,217	6,089
Net interest income	13,103	12,965	12,981	13,021	13,305	12,506	12,193	12,086	52,070	50,090
Provision for (recovery of) loan losses	403	(23)	23	(258)	(72)	(225)	49	161	145	(87)
Net interest income	12,700	12,988	12,958	13,279	13,377	12,731	12,144	11,925	51,925	50,177
Noninterest Income	8,674	1,570	3,094	1,539	1,634	1,623	1,607	1,544	14,877	6,408
Noninterest expense	11,155	9,425	10,215	9,959	9,318	10,200	9,607	11,266	40,754	40,391
Income (loss) before income taxes	10,219	5,133	5,837	4,859	5,693	4,154	4,144	2,203	26,048	16,194
Income tax expense	2,803	1,396	1,207	1,300	4,702	594	1,572	322	6,706	7,190
Net income (loss)	$ 7,416	$ 3,737	$ 4,630	$ 3,559	$ 991	$ 3,560	$ 2,572	$ 1,881	$ 19,342	$ 9,004
Earnings Per Share, Basic	$ 0.44	$ 0.22	$ 0.26	$ 0.20		$ 0.20	$ 0.14	$ 0.10	$ 1.11	$ 0.49
Diluted earnings (loss) per common share (usd per share)		$ 0.22	$ 0.26	$ 0.20	$ 0.06	$ 0.20	$ 0.14	$ 0.10	$ 1.11	$ 0.49