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Investments - Net Investment Income and Equity in Earnings of Investees (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Net Investment Income
Gross investment income	$ 82	$ 90	$ 167	$ 172
Investment expenses	(1)	(1)	(2)	(2)
Net investment income	81	89	165	170
Fair value gains (losses) on trading securities	17	40	43	38
Equity in Earnings (Losses) of Investees	5	5	29	7
Fair value gains (losses) on trading securities still held	14	40	31	38
Externally managed
Net Investment Income
Gross investment income	51	53	102	105
Loss Mitigation Securities
Net Investment Income
Gross investment income	7	12	14	22
Puerto Rico, New Recovery Bonds
Net Investment Income
Gross investment income	0	1	0	4
Other
Net Investment Income
Gross investment income	2	4	6	7
Short-term investments
Net Investment Income
Gross investment income	22	18	45	32
Other
Net Investment Income
Gross investment income	0	2	0	2
Sound Point
Net Investment Income
Equity in Earnings (Losses) of Investees	(3)	0	1	0
Funds
Net Investment Income
Equity in Earnings (Losses) of Investees	5	0	19	0
Equity method investments
Net Investment Income
Equity in Earnings (Losses) of Investees	$ 3	$ 5	$ 9	$ 7

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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, 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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