Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Data [Line Items]
Interest and dividend income	$ 9,294	$ 9,131	$ 8,923	$ 8,654	$ 8,571	$ 8,095	$ 7,943	$ 7,571	$ 36,002	$ 32,180
Interest expense	1,488	1,497	1,401	1,230	1,117	1,086	731	647	5,616	3,581
Net interest income	7,806	7,634	7,522	7,424	7,454	7,009	7,212	6,924	30,386	28,599
Provision for loan losses	425	150	150	50	150	150	150	0	775	450
Noninterest income	2,969	2,732	2,452	2,170	2,398	2,452	2,152	2,471	10,323	9,473
Noninterest expenses	7,135	7,001	6,807	6,513	10,322	6,525	6,306	6,124	27,456	29,277
Net income	$ 2,759	$ 2,738	$ 2,530	$ 2,621	$ (436)	$ 2,311	$ 2,450	$ 2,747	$ 10,648	$ 7,072
Earnings per common share	$ 0.61	$ 0.62	$ 0.56	$ 0.59	$ (0.10)	$ 0.52	$ 0.54	$ 0.62	$ 2.38	$ 1.58