Other Comprehensive (Loss) Income - Summary of Other Comprehensive (Loss) Income and Tax Impact of Each Component of Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Other comprehensive (loss) income
Change in unrealized (losses) gains on investments, net, Pre-tax	$ 3,625	$ 14,823	$ (6,972)	$ 16,850
Reclassification adjustment of realized gains included in net income, Pre-tax	(22)	38	(102)	(22)
Effect on other comprehensive (loss) income, Pre-tax	3,603	14,861	(7,074)	16,828
Change in unrealized (losses) gains on investments, net, Tax	(840)	(3,431)	1,616	(3,900)
Reclassification adjustment of realized gains included in net income, Tax	5	(9)	24	5
Effect on other comprehensive (loss) income, Tax	(835)	(3,440)	1,640	(3,895)
Change in unrealized (losses) gains on investments, net, After-tax	2,785	11,392	(5,356)	12,950
Reclassification adjustment of realized gains included in net income, After-tax	(17)	29	(78)	(17)
Effect on other comprehensive (loss) income, After-tax	$ 2,768	$ 11,421	$ (5,434)	$ 12,933

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

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