Net Income Per Share (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	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income available to common shareholders									$ 14,017	$ 8,640	$ 7,385
Weighted average shares outstanding (shares)									16,899,960	16,885,587	16,881,379
Add: dilutive effect of stock options (shares)									38,812	19,328	7,648
Weighted average shares outstanding adjusted for potential dilution (shares)									16,938,772	16,904,915	16,889,027
Basic earnings per share (dollars per share)	$ 0.23	$ 0.21	$ 0.20	$ 0.19	$ 0.10	$ 0.16	$ 0.15	$ 0.10	$ 0.83	$ 0.51	$ 0.44
Diluted earnings per share (dollars per share)	$ 0.23	$ 0.21	$ 0.20	$ 0.19	$ 0.10	$ 0.16	$ 0.15	$ 0.10	$ 0.83	$ 0.51	$ 0.44
Anti-dilutive shares excluded from earnings per share calculation (shares)									84,000	98,000	21,000