Investments - Net Investment Income and Equity in Earnings of Investees (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Net Investment Income
Gross investment income	$ 100	$ 90	$ 194	$ 178
Investment expenses	(2)	(1)	(4)	(2)
Net investment income	98	89	190	176
Fair value gains (losses) on trading securities	7	2	13	3
Equity in Earnings (Losses) of Investees	(11)	3	20	56
Fixed-maturity securities, available-for-sale:
Net Investment Income
Gross investment income	91	77	176	151
Short-term investments
Net Investment Income
Gross investment income	8	12	16	25
Other invested assets
Net Investment Income
Gross investment income	1	1	2	2
Sound Point
Net Investment Income
Equity in Earnings (Losses) of Investees	(5)	(1)	1	12
Equity method investments
Net Investment Income
Equity in Earnings (Losses) of Investees	(6)	4	19	44
Insured Financial Obligations, Loss Mitigation Securities
Net Investment Income
Gross investment income	3	7	6	14
Fixed-Maturity Securities, Trading
Net Investment Income
Fair value gains (losses) on trading securities still held	$ 7	$ 2	$ 12	$ 3

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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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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