Investments - Net Gains (Losses) On Investments and Other Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Fixed income securities
Gross realized gains on sales of fixed income securities	$ 425	$ 107	$ 480	$ 166
Gross realized losses on sales of fixed income securities	(1,262)	(6,415)	(6,747)	(10,548)
Equity securities gains (losses)
Equity securities, gains (losses), market adjustment	(92)	(164)	(195)	196
Change in embedded derivative on Home Re Transactions	646	1,497	(2,330)	(2,479)
Other
Other, gains (losses) on sales	16	(6)	17	0
Other, market adjustment	(9)	(6)	(10)	(20)
Net gains (losses) on investments and other financial instruments	(276)	(4,987)	(8,785)	(12,685)
Proceeds from sales of fixed income securities	$ 0	$ 236,777	$ 14,886	$ 268,958

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
-Topic 320
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-Name Accounting Standards Codification
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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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-Name Accounting Standards Codification
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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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