Investments - Net Gains (Losses) On Investments and Other Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Fixed income securities
Gross realized gains on sales of fixed income securities	$ 28	$ 2,581	$ 508	$ 2,747
Gross realized losses on sales of fixed income securities	(946)	(2,814)	(7,693)	(13,362)
Equity securities gains (losses)
Equity securities, gains (losses), market adjustment	507	(462)	312	(266)
Change in embedded derivative on Home Re Transactions	994	(7)	(1,336)	(2,486)
Other
Other, gains (losses) on sales	0	(4)	17	(4)
Other, market adjustment	0	11	(10)	(9)
Net gains (losses) on investments and other financial instruments	583	(695)	(8,202)	(13,380)
Proceeds from sales of fixed income securities	$ 14,856	$ 24,434	$ 29,742	$ 293,392

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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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