Investments - Net Investment Income and Equity in Earnings of Investees (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Net Investment Income
Gross investment income	$ 105	$ 96	$ 299	$ 274
Investment expenses	(2)	(2)	(6)	(4)
Net investment income	103	94	293	270
Fair value gains (losses) on trading securities	(2)	8	11	11
Equity in Earnings (Losses) of Investees	12	20	32	76
Fixed-maturity securities, available-for-sale:
Net Investment Income
Gross investment income	93	81	269	232
Short-term investments
Net Investment Income
Gross investment income	8	14	24	39
Other invested assets
Net Investment Income
Gross investment income	4	1	6	3
Sound Point
Net Investment Income
Equity in Earnings (Losses) of Investees	2	0	3	12
Equity method investments
Net Investment Income
Equity in Earnings (Losses) of Investees	10	20	29	64
Insured Financial Obligations, Loss Mitigation Securities
Net Investment Income
Gross investment income	3	7	9	21
Fixed-Maturity Securities, Trading
Net Investment Income
Fair value gains (losses) on trading securities still held	$ (2)	$ 7	$ 5	$ 9

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 income (loss) for proportionate share of equity method investee's income (loss).

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Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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