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Investments - Net Investment Income and Equity in Earnings of Investees (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Net Investment Income
Gross investment income	$ 96	$ 83	$ 274	$ 250
Investment expenses	(2)	(1)	(4)	(3)
Net investment income	94	82	270	247
Fair value gains (losses) on trading securities	8	9	11	52
Equity in Earnings (Losses) of Investees	20	18	76	47
Fixed-maturity securities, available-for-sale
Net Investment Income
Gross investment income	81	62	232	184
Short-term investments
Net Investment Income
Gross investment income	14	21	39	66
Other
Net Investment Income
Gross investment income	1	0	3	0
Sound Point
Net Investment Income
Equity in Earnings (Losses) of Investees	0	4	12	5
Equity method investments
Net Investment Income
Equity in Earnings (Losses) of Investees	20	14	64	42
Insured Financial Obligations, Loss Mitigation Securities
Net Investment Income
Gross investment income	7	7	21	21
Fixed-Maturity Securities, Trading
Net Investment Income
Fair value gains (losses) on trading securities still held	$ 7	$ 7	$ 9	$ 26

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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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