Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Net income	$ 140,461	$ 170,957
Unrealized gains (losses) on investments:
Unrealized holding gains (losses) arising during the period	(72,293)	78,023
Less: Reclassification adjustment for net gains (losses) included in net income	8,394	(391)
Net unrealized gains (losses) on investments	(80,687)	78,414
Other comprehensive income (loss), net of tax	(80,687)	78,414
Comprehensive income	$ 59,774	$ 249,371

Other Comprehensive Gain (Loss), Unrealized Holding Gains (Losses) on Investments [Abstract]

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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 and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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

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

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