Investments - Components of Net Realized Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Components of net realized capital gains (losses)
Net realized losses	$ (265)	$ (258)	$ (400)	$ (361)
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	(208)	(192)	(340)	(252)
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	(57)	(66)	(60)	(109)
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales and impairments of fixed maturity securities	(63)	(151)	(193)	(413)
Change in allowance for credit losses on fixed maturity securities	3	(15)	2	(7)
Foreign exchange transactions	(7)	(14)	(29)	212
Derivatives and hedge accounting	(22)	(114)	(16)	(148)
Sales of alternative investments	(38)	3	(16)	3
Other	(86)	(3)	(140)	(12)
Net realized losses	(214)	(244)	(359)	(306)
Excluding modified coinsurance and funds withheld embedded derivative \| Loans Receivable
Components of net realized capital gains (losses)
Change in allowance for credit losses on loans	(1)	50	33	59
Excluding modified coinsurance and funds withheld embedded derivative \| Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Sales and impairments of fixed maturity securities	(59)	(102)	(174)	(357)
Change in allowance for credit losses on fixed maturity securities	3	(15)	1	(7)
Foreign exchange transactions	(8)	(27)	(27)	193
Derivatives and hedge accounting	(20)	(98)	(18)	(126)
Sales of alternative investments	(38)	3	(16)	3
Other	(85)	2	(138)	(8)
Net realized losses	(208)	(192)	(340)	(252)
Excluding modified coinsurance and funds withheld embedded derivative \| Excluding Fortitude Re Funds Withheld Assets \| Loans Receivable
Components of net realized capital gains (losses)
Change in allowance for credit losses on loans	(1)	45	32	50
Excluding modified coinsurance and funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Sales and impairments of fixed maturity securities	(4)	(49)	(19)	(56)
Change in allowance for credit losses on fixed maturity securities	0	0	1	0
Foreign exchange transactions	1	13	(2)	19
Derivatives and hedge accounting	(2)	(16)	2	(22)
Sales of alternative investments	0	0	0	0
Other	(1)	(5)	(2)	(4)
Net realized losses	(6)	(52)	(19)	(54)
Excluding modified coinsurance and funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets \| Loans Receivable
Components of net realized capital gains (losses)
Change in allowance for credit losses on loans	0	5	1	9
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized losses	(51)	(14)	(41)	(55)
Fortitude Re funds withheld embedded derivative \| Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	0	0	0	0
Fortitude Re funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	$ (51)	$ (14)	$ (41)	$ (55)

Gain Loss On Sale Of Alternative Investments

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Represents other investment charges not specified in the taxonomy.

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- Definition

Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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- Definition

Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction.

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Amount of realized and unrealized gain (loss) on investment.

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The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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