Investments - Net Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Fixed maturity securities available-for-sale:
Gross realized gains	$ 1,224	$ 2,014	$ 1,578	$ 2,383
Gross realized (losses)	(3,508)	(8,306)	(9,672)	(11,803)
Net realized gains (losses)	(2,284)	(6,292)	(8,094)	(9,420)
Write-down of available-for-sale fixed maturity securities	0	1,254	0	1,254
Change in allowance for credit losses on fixed maturity securities	0	273	0	0
Other	50	(70)	37	88
Net investment gains (losses)	$ (2,234)	$ (7,343)	$ (8,057)	$ (10,586)

Other Investment Gains (Losses)

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- Definition

Amount of impairment loss for asset. Includes, but is not limited to, tangible and intangible assets and goodwill.

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Amount of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized and unrealized gain (loss) on investment.

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