Investments - Net Gains (Losses) On Investments and Other Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Fixed income securities:
Gross realized gains on sales of fixed income securities	$ 427	$ 28	$ 1,351	$ 508
Gross realized losses on sales of fixed income securities	(36)	(946)	(2,585)	(7,693)
Equity securities gains (losses):
Equity securities, gains (losses), market adjustment	212	507	421	312
Change in embedded derivative on Home Re Transactions(1)	(441)	994	290	(1,336)
Other:
Other, gains (losses) on sales	0	0	0	17
Other, market adjustment	0	0	0	(10)
Net gains (losses) on investments and other financial instruments	162	583	(523)	(8,202)
Proceeds from sales of fixed income securities	$ 21,480	$ 14,856	$ 62,497	$ 29,742

Fixed Income Securities

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Amount of realized and unrealized gain (loss) on investments and other financial instruments, including the changes in fair value of embedded derivatives related to Home Re Transactions.

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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 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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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of gain (loss) included in earnings for investments classified as other.

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Amount of cash inflow from sale 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 unrealized gain (loss) on investment.

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