Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income, Before tax amount	$ 3,434	$ 3,231	$ 6,926	$ 7,213
Net unrealized holding (losses) gains on securities:
Unrealized holding (losses) gains arising during the period, Before tax amount	(1,217)	1,682	(6,263)	2,931
Reclassification adjustment for gains included in net income, Before tax amount	(2)	(115)	(3)	(864)
Unrealized holding (losses) gains arising during the period, Tax expense (benefit)	(255)	572	(1,315)	997
Reclassification adjustment for gains included in net income, Tax expense (benefit)	(1)	(40)	(1)	(294)
Unrealized holding (losses) gains arising during the period, Net of tax amount	(962)	1,110	(4,948)	1,934
Reclassification adjustment for gains included in net income, Net of tax amount	(1)	(75)	(2)	(570)
Other comprehensive (loss) income, Before tax amount	(1,219)	1,567	(6,266)	2,067
Total comprehensive (loss) income, Before tax amount	2,215	4,798	660	9,280
Tax expense (benefit)	572	845	1,129	1,967
Other comprehensive (loss) income, Tax expense (benefit)	(256)	532	(1,316)	703
Total comprehensive (loss) income,Tax expense (benefit)	316	1,377	(187)	2,670
Net income	2,862	2,386	5,797	5,246
Other comprehensive (loss) income, Net of tax amount	(963)	1,035	(4,950)	1,364
Total comprehensive (loss) income, Net of tax amount	$ 1,899	$ 3,421	$ 847	$ 6,610