Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 643,867	$ 605,224
Reclassification from other comprehensive (income) loss	726
Other comprehensive income (loss)	6	(239)
Ending Balance	646,458	625,406
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		(249)
Reclassification from other comprehensive (income) loss	726	178
Other comprehensive income (loss)	726	(71)
Ending Balance	0	(683)
Other comprehensive income (loss), before reclassifications, tax		97
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	6	10
Reclassification from other comprehensive (income) loss	0	0
Other comprehensive income (loss)	6	10
Ending Balance	1	22
Other comprehensive income (loss), before reclassifications, tax	$ (3)	$ (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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