Investments - Components of net realized gains (losses) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Components of net realized capital gains (losses)
Sales of fixed maturity securities	$ (163)	$ (131)	$ (956)	$ (874)
Net realized gains	1,081	2,572	(1,125)	8,783
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains	171	901	(881)	1,244
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains	910	1,671	(244)	7,539
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(163)	(131)	(956)	(874)
Change in allowance for credit losses on fixed maturity securities	(54)	6	(128)	(135)
Foreign exchange transactions	(203)	(264)	149	(530)
Index-linked interest credited embedded derivatives, net of related hedges	129	34	(190)	217
All other derivatives and hedge accounting*	228	1,031	(12)	2,105
Sales of alternative investments and real estate investments	64	169	72	195
Other	6	20	(35)	1
Net realized gains	(56)	815	(1,277)	932
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	(63)	(50)	(177)	(47)
Excluding modified coinsurance and funds withheld embedded derivative \| Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(157)	(67)	(831)	(656)
Change in allowance for credit losses on fixed maturity securities	(47)	(1)	(119)	(101)
Foreign exchange transactions	(165)	(242)	160	(484)
Index-linked interest credited embedded derivatives, net of related hedges	129	34	(190)	217
All other derivatives and hedge accounting*	377	1,044	186	2,126
Sales of alternative investments and real estate investments	65	137	73	160
Other	10	22	(31)	3
Net realized gains	171	901	(881)	1,244
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	(41)	(26)	(129)	(21)
Excluding modified coinsurance and funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(6)	(64)	(125)	(218)
Change in allowance for credit losses on fixed maturity securities	(7)	7	(9)	(34)
Foreign exchange transactions	(38)	(22)	(11)	(46)
Index-linked interest credited embedded derivatives, net of related hedges	0	0	0	0
All other derivatives and hedge accounting*	(149)	(13)	(198)	(21)
Sales of alternative investments and real estate investments	(1)	32	(1)	35
Other	(4)	(2)	(4)	(2)
Net realized gains	(227)	(86)	(396)	(312)
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	(22)	(24)	(48)	(26)
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized gains	1,137	1,757	152	7,851
Fortitude Re funds withheld embedded derivative \| Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains	0	0	0	0
Fortitude Re funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains	$ 1,137	$ 1,757	$ 152	$ 7,851

Gain Loss On Sale Of Alternative And Real Estate 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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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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- Definition

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

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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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