Investments - Net Investment Income and Equity in Earnings of Investees (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Net Investment Income
Gross investment income	$ 85	$ 82
Investment expenses	(1)	(1)
Net investment income	84	81
Fair value gains (losses) on trading securities	26	(2)
Equity in Earnings (Losses) of Investees	24	2
Fair value gains (losses) on trading securities still held	22	(2)
Externally managed
Net Investment Income
Gross investment income	51	52
Loss Mitigation Securities
Net Investment Income
Gross investment income	7	9
Puerto Rico, New Recovery Bonds
Net Investment Income
Gross investment income	0	3
Other
Net Investment Income
Gross investment income	4	5
Short-term investments
Net Investment Income
Gross investment income	23	13
Sound Point
Net Investment Income
Equity in Earnings (Losses) of Investees	4	0
Funds
Net Investment Income
Equity in Earnings (Losses) of Investees	14	0
Equity method investments
Net Investment Income
Equity in Earnings (Losses) of Investees	$ 6	$ 2

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 unrealized gain (loss) recognized in income from asset (liability) measured at fair value on recurring basis using unobservable input (level 3) and still held.

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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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