Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Unrealized gains (losses) on available-for-sale securities:
Balance, beginning of period	$ 4	$ 259	$ (65)	$ (62)
Other comprehensive income (loss) before reclassifications	40	(10)	187	478
Amounts reclassified from accumulated other comprehensive income (loss)	(3)	(6)	(45)	(8)
Income taxes	(12)	5	(48)	(160)
Net current-period other comprehensive income (loss)	25	(11)	94	310
Balance, end of period	$ 29	$ 248	$ 29	$ 248

Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

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