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Investments and Cash - Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Investment Income
Gross investment income	$ 370	$ 274	$ 275
Investment expenses	(5)	(5)	(6)
Net investment income	365	269	269
Fair value gains (losses) on trading securities	74	(34)	0
Equity in earnings (losses) of investees	28	(39)	94
Fair value loss on trading securities still held	$ 31	(29)
Fair Value, Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Fair value gains (losses) on trading securities
Externally managed
Net Investment Income
Gross investment income	$ 207	201	212
Loss Mitigation Securities
Net Investment Income
Gross investment income	55	31	38
Puerto Rico, New Recovery Bonds
Net Investment Income
Gross investment income	12	7	0
Other
Net Investment Income
Gross investment income	20	19	24
Short-term investments
Net Investment Income
Gross investment income	73	15	0
Other Investments
Net Investment Income
Gross investment income	3	1	1
Sound Point
Net Investment Income
Equity in earnings (losses) of investees	5	0	0
Equity Funds
Net Investment Income
Equity in earnings (losses) of investees	15	2	30
Other
Net Investment Income
Equity in earnings (losses) of investees	$ 8	$ (41)	$ 64

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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 of income (loss) for proportionate share of equity method investee's income (loss).

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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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