Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement Of Income and Comprehensive Income [Abstract]
Net income	$ 89	$ 11
Unrealized holding gains (losses) on available-for-sale securities
Unrealized holding gains (losses) arising during the period	(118)	15
Net unrealized gain (loss) on available for sale securities	(118)	15
Other comprehensive income (loss), before tax	(118)	15
Tax effect	(26)	5
Other comprehensive income (loss), net of tax	(92)	10
Comprehensive income (loss)	(3)	21
Tax Effect Allocated to Each Component of Other Comprehensive Income
Unrealized holding gains (losses) arising during the period	(26)	5
Income tax effect related to other comprehensive income (loss)	$ (26)	$ 5

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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