Investments - Net Gains (Losses) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Fixed-maturities available for sale
Net realized gains (losses) on investments sold or redeemed	$ 808	$ 2,401	$ (2,686)	$ (4,299)
Change in unrealized gains (losses) on residential mortgage loans sold	(847)	(2,025)	(1,282)	(690)
Impairment losses due to intent to sell	0	(131)	0	(369)
Net unrealized gains (losses) on investments still held
Net unrealized gains (losses) on investments still held	294	6,559	1,785	5,785
Total net gains (losses) on investments	255	6,804	(2,183)	427
Net gains (losses) on other financial instruments	1,030	(83)	3,318	1,976
Net gains (losses) on investments and other financial instruments	1,285	6,721	1,135	2,403
Fixed-maturities available for sale
Fixed-maturities available for sale
Gross realized gains	64	2,021	526	2,652
Gross realized losses	(933)	(1,324)	(5,801)	(8,472)
Fixed-maturities available for sale, net	(869)	697	(5,275)	(5,820)
Fixed maturities trading securities
Fixed-maturities available for sale
Trading securities	(54)	(496)	(54)	(686)
Net unrealized gains (losses) on investments still held
Trading securities	1,048	3,926	3,267	988
Equity securities
Fixed-maturities available for sale
Equity securities	1,683	2,156	2,581	2,162
Net unrealized gains (losses) on investments still held
Equity securities	(1,570)	2,585	(2,275)	4,739
Other investments
Fixed-maturities available for sale
Other investments	48	44	62	45
Net unrealized gains (losses) on investments still held
Other investments	$ 816	$ 48	$ 793	$ 58

Change In Unrealized Gains (Losses) On Investments Sold Or Redeemed

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Amount of unrealized holding gain (loss) recognized in the income statement for investments in equity securities and securities classified as trading.

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Amount of the change in unrealized holding gain (loss) recognized in the income statement for investments in equity securities.

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Gain (Loss) On Financial Instruments

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Gain (Loss) On Investments And Financial Instruments

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Other Investments, Change in Unrealized Holding Gain (Loss)

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This amount represents the net realized gains (losses) on all fixed-maturities, equity, trading, short-term, and other-invested assets securities, excluding other-than-temporary impairments and net unrealized gains (losses) on investment securities.

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Securities, Trading, Realized Gain (Loss)

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Unrealized Gains (Losses) on Investments

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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of writeoff of allowance for credit 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 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 unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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

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