Investments - Net Investment Income and Equity in Earnings of Investees (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Net Investment Income
Gross investment income	$ 88	$ 85
Investment expenses	(1)	(1)
Net investment income	87	84
Fair value gains (losses) on trading securities	1	26
Equity in Earnings (Losses) of Investees	53	24
Available-for-Sale Securities
Net Investment Income
Gross investment income	74	62
Short-term investments
Net Investment Income
Gross investment income	13	23
Other
Net Investment Income
Gross investment income	1	0
Sound Point
Net Investment Income
Equity in Earnings (Losses) of Investees	13	4
Equity method investments
Net Investment Income
Equity in Earnings (Losses) of Investees	40	20
Insured Financial Obligations, Loss Mitigation Securities
Net Investment Income
Gross investment income	$ 7	7
Fixed-Maturity Securities, Trading
Net Investment Income
Fair value gains (losses) on trading securities still held		$ 22

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 of expenses related to the generation of investment income.

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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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