Other Comprehensive Income - Summary of Other Comprehensive Income (Loss) and Tax Impact of Each Component of Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Other comprehensive income
Change in unrealized losses on investments, net, Pre-tax	$ 2,480	$ 4,429	$ 19,330	$ 19,533
Reclassification adjustment of realized losses (gains) included in net income, Pre-tax	(20,355)	(103)	(20,377)	291
Effect on other comprehensive income, Pre-tax	(17,875)	4,326	(1,047)	19,824
Change in unrealized losses on investments, net, Tax	(574)	(1,060)	(4,471)	(4,677)
Reclassification adjustment of realized losses (gains) included in net income, Tax	4,711	25	4,713	(70)
Effect on other comprehensive income, Tax	4,137	(1,035)	242	(4,747)
Change in unrealized losses on investments, net, After-tax	1,906	3,369	14,859	14,856
Reclassification adjustment of realized losses (gains) included in net income, After-tax	(15,644)	(78)	(15,664)	221
Effect on other comprehensive income, After-tax	$ (13,738)	$ 3,291	$ (805)	$ 15,077

Amount before tax of other comprehensive income (loss) attributable to parent entity.

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