Selected Quarterly Financial Data (Unaudited) (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	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Interest income	$ 42,637	$ 42,847	$ 40,193	$ 39,466	$ 38,948	$ 37,727	$ 35,935	$ 34,682	$ 165,143	$ 147,292	$ 132,869
Interest expense	14,161	14,027	13,034	12,136	10,944	9,803	8,165	7,138	53,358	36,050	23,976
Net interest income	28,476	28,820	27,159	27,330	28,004	27,924	27,770	27,544	111,785	111,242	108,893
Provision for loan losses	772	(1,300)	491	59	607	1,304	670	34	22	2,615	1,411
Net interest income after provision for loan losses	27,704	30,120	26,668	27,271	27,397	26,620	27,100	27,510	111,763	108,627	107,482
Other income	4,195	4,733	2,566	3,314	640	2,637	2,445	2,405	14,808	8,127	11,642
Other expenses	18,726	16,869	18,750	19,204	15,777	17,100	17,040	17,126	73,549	67,043	67,378
Income before income tax expense	13,173	17,984	10,484	11,381	12,260	12,157	12,505	12,789	53,022	49,711	51,746
Income tax expense	3,052	4,845	2,280	2,610	2,314	3,081	1,893	2,344	12,787	9,632	26,978
Net income	$ 10,121	$ 13,139	$ 8,204	$ 8,771	$ 9,946	$ 9,076	$ 10,612	$ 10,445	$ 40,235	$ 40,079	$ 24,768
Net income per basic common share (dollars per share)	$ 0.22	$ 0.28	$ 0.18	$ 0.19	$ 0.21	$ 0.19	$ 0.23	$ 0.23	$ 0.86	$ 0.87	$ 0.55
Net income per diluted common share (dollars per share)	$ 0.21	$ 0.28	$ 0.17	$ 0.19	$ 0.21	$ 0.19	$ 0.23	$ 0.22	$ 0.85	$ 0.85	$ 0.53