Investments - Components of net realized gains (losses) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Components of net realized capital gains (losses)
Sales of fixed maturity securities	$ (604)	$ 135	$ (743)	$ 524
Change in allowance for credit losses on loans	14	86	22	113
Net realized gains (losses)	3,392	(1,926)	7,811	1,324
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	702	(43)	1,943	652
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	2,690	(1,883)	5,868	672
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(604)	135	(743)	524
Change in allowance for credit losses on fixed maturity securities	(48)	14	(141)	67
Foreign exchange transactions	(246)	148	(269)	93
Variable annuity embedded derivatives, net of related hedges	454	(53)	960	36
All other derivatives and hedge accounting	1,018	(276)	1,901	(42)
Sales of alternative investments and real estate investments	9	28	26	58
Other	3	59	(20)	151
Net realized gains (losses)	616	130	1,717	998
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	30	75	3	111
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	(482)	40	(589)	134
Change in allowance for credit losses on fixed maturity securities	(47)	10	(100)	61
Foreign exchange transactions	(231)	139	(245)	90
Variable annuity embedded derivatives, net of related hedges	454	(53)	960	36
All other derivatives and hedge accounting	970	(336)	1,909	15
Sales of alternative investments and real estate investments	7	31	23	57
Other	7	59	(20)	151
Net realized gains (losses)	702	(43)	1,943	652
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	24	67	5	108
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	(122)	95	(154)	390
Change in allowance for credit losses on fixed maturity securities	(1)	4	(41)	6
Foreign exchange transactions	(15)	9	(24)	3
Variable annuity embedded derivatives, net of related hedges	0	0	0	0
All other derivatives and hedge accounting	48	60	(8)	(57)
Sales of alternative investments and real estate investments	2	(3)	3	1
Other	(4)	0	0	0
Net realized gains (losses)	(86)	173	(226)	346
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	6	8	(2)	3
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized gains (losses)	2,776	(2,056)	6,094	326
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	0
Fortitude Re funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	$ 2,776	$ (2,056)	$ 6,094	$ 326

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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Amount 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 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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Amount of credit loss expense (reversal of expense) for financing receivable.

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