Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 663,672	$ 640,366	$ 643,867	$ 605,224
Reclassification from other comprehensive (income) loss			726
Other comprehensive income (loss)	(12)	22	(14)	(178)
Ending Balance	677,616	659,225	677,616	659,225
Unrealized Net Gains and (Losses) on Securities Available-for-Sale
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			(726)	(612)
Other comprehensive income (loss), before reclassifications				(168)
Reclassification from other comprehensive (income) loss			726	178
Other comprehensive income (loss)			726	10
Ending Balance	0	(602)	0	(602)
Other comprehensive income (loss), before reclassifications, tax				68
Reclassification from AOCI, tax			(254)	(61)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			(5)	12
Other comprehensive income (loss), before reclassifications			(14)	(10)
Reclassification from other comprehensive (income) loss			0	0
Other comprehensive income (loss)			(14)	(10)
Ending Balance	$ (19)	$ 2	(19)	2
Other comprehensive income (loss), before reclassifications, tax			$ 5	$ 4

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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