Investments - Components of net realized gains (losses) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Components of net realized capital gains (losses)
Sales of fixed maturity securities	$ (1,200)	$ 928	$ 1,000
Change in allowance for credit losses on loans	(104)	164	(75)
Net realized gains (losses)	8,991	2,151	(2,238)
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	1,996	1,751	(56)
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	6,995	400	(2,182)
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(1,182)	928	1,014
Intent to sell	(66)	0	(3)
Change in allowance for credit losses on fixed maturity securities	(216)	26	(280)
Foreign exchange transactions	(22)	11	378
Variable annuity embedded derivatives, net of related hedges	1,221	(39)	166
All other derivatives and hedge accounting	1,680	207	(921)
Sales of alternative investments and real estate investments	236	1,225	143
Other	(39)	224	13
Net realized gains (losses)	1,510	2,754	407
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	(102)	172	(103)
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	(871)	211	307
Intent to sell	(66)	0	(3)
Change in allowance for credit losses on fixed maturity securities	(184)	19	(270)
Foreign exchange transactions	(17)	16	365
Variable annuity embedded derivatives, net of related hedges	1,221	(39)	166
All other derivatives and hedge accounting	1,814	179	(672)
Sales of alternative investments and real estate investments	193	988	143
Other	(39)	214	13
Net realized gains (losses)	1,996	1,751	(56)
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	(55)	163	(105)
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	(311)	717	707
Intent to sell	0	0	0
Change in allowance for credit losses on fixed maturity securities	(32)	7	(10)
Foreign exchange transactions	(5)	(5)	13
Variable annuity embedded derivatives, net of related hedges	0	0	0
All other derivatives and hedge accounting	(134)	28	(249)
Sales of alternative investments and real estate investments	43	237	0
Other	0	10	0
Net realized gains (losses)	(486)	1,003	463
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	(47)	9	2
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized gains (losses)	7,481	(603)	(2,645)
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)	$ 7,481	$ (603)	$ (2,645)

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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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 foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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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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