Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance	$ 643,867	$ 605,224	$ 321,673
Reclassification from other comprehensive (income) loss	726
Other comprehensive income (loss)	14	(309)	(376)
Balance	686,257	643,867	605,224
Unrealized Gains (Losses) on Securities Available-for-Sale
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance	(726)	(612)
Unrealized net gain (loss) on available-for-sale securities and foreign currency translation adjustments, net of tax	0	(292)
Reclassification from other comprehensive (income) loss	726	178
Other comprehensive income (loss)	726	(114)
Balance	0	(726)	(612)
Other comprehensive income (loss) before reclassification, tax		111
Reclassification from AOCI, tax	(254)	(61)
Foreign Currency Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance	(5)	12
Unrealized net gain (loss) on available-for-sale securities and foreign currency translation adjustments, net of tax	14	(17)
Reclassification from other comprehensive (income) loss	0	0
Other comprehensive income (loss)	14	(17)
Balance	9	(5)	$ 12
Other comprehensive income (loss) before reclassification, tax	$ 5	6
Reclassification from AOCI, tax		$ (1)

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

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