Investments - Net Gains (Losses) On Investments and Other Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Fixed income securities
Gross realized gains on sales of fixed income securities	$ 2,581	$ 1,667	$ 2,747	$ 6,788
Gross realized losses on sales of fixed income securities	(2,814)	(7,040)	(13,362)	(12,790)
Impairments	0	(1,415)	0	(1,415)
Equity securities gains (losses)
Equity securities, gains (losses), market adjustment	(462)	(617)	(266)	(2,351)
Change in embedded derivative on Home Re Transactions	(7)	4,199	(2,486)	983
Other
Other, gains (losses) on sales	(4)	(66)	(4)	(18)
Other, market adjustment	11	14	(9)	27
Net gains (losses) on investments and other financial instruments	(695)	(3,258)	(13,380)	(8,776)
Proceeds from sales of fixed income securities	$ 24,434	$ 125,186	$ 293,392	$ 388,740

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 other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings.

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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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