Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 10,800	$ 19,400
Other comprehensive income:
Unrealized gain on debt securities, net of tax	1,484	5,992
Change in deferred tax valuation allowance		(198)
Comprehensive income	$ 12,284	$ 25,194

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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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