Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 1,026	$ 742	$ 3,096	$ 1,122
Other comprehensive (loss) income:
Unrealized holding (loss) gain on available-for-sale securities arising during the period	(477)	59	(1,944)	545
Deferred tax benefit (expense)	100	(20)	408	(185)
Reclassification of net available-for-sale securities gains recognized in net income				(2)
Deferred tax benefit				1
Total other comprehensive (loss) income	(377)	39	(1,536)	359
Comprehensive income	$ 649	$ 781	$ 1,560	$ 1,481

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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