Investments - Components of net realized gains (losses) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Components of net realized capital gains (losses)
Sales of fixed maturity securities	$ (452)	$ (139)
Net realized losses	(1,909)	3,579
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	(713)	401
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	(1,196)	3,178
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(452)	(139)
Change in allowance for credit losses on fixed maturity securities	(16)	(93)
Foreign exchange transactions	130	(22)
Index-linked interest credited embedded derivatives, net of related hedges	(178)	203
All other derivatives and hedge accounting*	(179)	344
Sales of alternative investments and real estate investments	5	17
Other	9	(22)
Net realized losses	(744)	261
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)	(27)
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	(387)	(107)
Change in allowance for credit losses on fixed maturity securities	(16)	(53)
Foreign exchange transactions	114	(13)
Index-linked interest credited embedded derivatives, net of related hedges	(178)	203
All other derivatives and hedge accounting*	(217)	400
Sales of alternative investments and real estate investments	4	16
Other	9	(26)
Net realized losses	(713)	401
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	(42)	(19)
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	(65)	(32)
Change in allowance for credit losses on fixed maturity securities	0	(40)
Foreign exchange transactions	16	(9)
Index-linked interest credited embedded derivatives, net of related hedges	0	0
All other derivatives and hedge accounting*	38	(56)
Sales of alternative investments and real estate investments	1	1
Other	0	4
Net realized losses	(31)	(140)
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	(21)	(8)
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized losses	(1,165)	3,318
Fortitude Re funds withheld embedded derivative \| Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	0	0
Fortitude Re funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized losses	$ (1,165)	$ 3,318

Gain Loss On Sale Of Alternative And Real Estate Investments

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- Definition

Represents other investment charges not specified in the taxonomy.

+ References

No definition available.

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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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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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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 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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No definition available.

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