Accumulated Other Comprehensive (Loss) Income - Components of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
AOCI Attributable to Parent, Net of Tax
Balance at the beginning of period, gross	$ 46,123	$ (29,760)
Unrealized holding gains (losses) on fixed maturity securities, gross	(77,066)	34,803
Amounts reclassified into net income, gross	942	(214)
Amounts reclassified as credit losses, gross	(416)
Other comprehensive (loss) income, gross	(77,592)	35,017
Balance at the end of period, gross	(31,469)	5,257
Balance at the beginning of period, tax	8,670	(7,445)
Unrealized holding gains (losses) on fixed income securities, tax	(16,102)	7,241
Amounts reclassified into net income, tax	136	(24)
Amounts reclassified as credit losses, tax expense (benefit)	(87)	0
Other comprehensive (loss) income, tax	(16,151)	7,265
Balance at the end of period, tax	(7,481)	(180)
Balance at the beginning of period, net	37,453	(22,315)
Unrealized holding gains (losses) on fixed income securities	(60,964)	27,562
Amounts reclassified into net income	806	(190)
Amounts reclassified as credit losses, net	(329)
Other comprehensive (loss) income	(61,441)	27,752
Balance at the end of period, net	$ (23,988)	$ 5,437

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

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for credit loss.

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Amount, net of tax, of reclassification adjustment from accumulated other comprehensive income (loss) for credit loss

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Tax expense on reclassification adjustment from accumulated other comprehensive income (loss) for credit loss.

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Amount of tax for reclassification adjustments of other comprehensive income (loss) attributable to parent.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, attributable to parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).

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Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss) attributable to parent.

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