Consolidated Statements of Comprehensive Income - 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	$ 946	$ 557	$ 2,070	$ 380
Other comprehensive (loss) income:
Unrealized holding (loss) gain on available-for-sale securities arising during the period	(272)	445	(1,467)	485
Deferred tax benefit (expense)	57	(150)	308	(164)
Reclassification of net available-for-sale securities gains recognized in net income		(7)		(2)
Deferred tax benefit		2		1
Total other comprehensive (loss) income	(215)	290	(1,159)	320
Comprehensive income	$ 731	$ 847	$ 911	$ 700

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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