Investments - Components of net realized gains (losses) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of net realized capital gains (losses)
Sales of fixed maturity securities	$ (1,100)	$ (1,200)	$ 928
Change in allowance for credit losses on loans			164
Net realized gains (losses)	(4,608)	7,064	2,271
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	(2,306)	69	1,871
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	(2,302)	6,995	400
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(1,062)	(1,182)	928
Intent to sell	0	(66)	0
Change in allowance for credit losses on fixed maturity securities	(220)	(216)	26
Foreign exchange transactions	120	(25)	17
Index-linked interest credited embedded derivatives, net of related hedges	(784)	(119)	(5)
All other derivatives and hedge accounting*	(479)	1,096	288
Sales of alternative investments and real estate investments	96	236	1,225
Other	(43)	(39)	223
Net realized gains (losses)	(2,601)	(417)	2,874
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	(229)	(102)	172
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	(929)	(871)	211
Intent to sell	0	(66)	0
Change in allowance for credit losses on fixed maturity securities	(211)	(184)	19
Foreign exchange transactions	101	(20)	22
Index-linked interest credited embedded derivatives, net of related hedges	(784)	(119)	(5)
All other derivatives and hedge accounting*	(374)	1,230	260
Sales of alternative investments and real estate investments	98	193	988
Other	(40)	(39)	213
Net realized gains (losses)	(2,306)	69	1,871
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	(167)	(55)	163
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	(133)	(311)	717
Intent to sell	0		0
Change in allowance for credit losses on fixed maturity securities	(9)	(32)	7
Foreign exchange transactions	19	(5)	(5)
Index-linked interest credited embedded derivatives, net of related hedges	0	0	0
All other derivatives and hedge accounting*	(105)	(134)	28
Sales of alternative investments and real estate investments	(2)	43	237
Other	(3)	0	10
Net realized gains (losses)	(295)	(486)	1,003
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	(62)	(47)	9
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized gains (losses)	(2,007)	7,481	(603)
Fortitude Re funds withheld embedded derivative \| Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	0	0	0
Fortitude Re funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	$ (2,007)	$ 7,481	$ (603)

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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Realized Gains (Losses), Change In Intent

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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).

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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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- 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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