Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Basic
Net income	$ 4,740	$ 3,216
Undistributed earnings allocated to participating securities	(127)	(106)
Net income allocated to common shares	$ 4,613	$ 3,110
Weighted average common shares outstanding	15,817,060	13,292,083
Basic earnings per common share	$ 0.29	$ 0.23
Diluted
Net income allocated to common shares	$ 4,613	$ 3,110
Weighted average common shares outstanding	15,817,060	13,292,083
Add: Dilutive effects of assumed exercises of stock options	295,665	534,873
Average shares and dilutive potential common shares	16,112,725	13,826,956
Diluted earnings per common share	$ 0.29	$ 0.22