Investments - Components of Net Realized Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Components of net realized capital gains (losses)
Sales of fixed maturity securities	$ (443)	$ (452)
Net realized gains (losses)	(424)	(1,909)
Excluding Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	(258)	(713)
Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	(166)	(1,196)
Excluding modified coinsurance and funds withheld embedded derivative
Components of net realized capital gains (losses)
Sales of fixed maturity securities	(443)	(452)
Intent to sell	(48)	0
Change in allowance for credit losses on fixed maturity securities	(68)	(16)
Foreign exchange transactions	0	130
Index-linked interest credited embedded derivatives, net of related hedges	90	(178)
All other derivatives and hedge accounting	33	(179)
Sales of alternative investments and real estate investments	29	5
Other	(8)	9
Net realized gains (losses)	(437)	(744)
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	(22)	(63)
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	(406)	(387)
Intent to sell	(16)	0
Change in allowance for credit losses on fixed maturity securities	(62)	(16)
Foreign exchange transactions	14	114
Index-linked interest credited embedded derivatives, net of related hedges	90	(178)
All other derivatives and hedge accounting	123	(217)
Sales of alternative investments and real estate investments	30	4
Other	(8)	9
Net realized gains (losses)	(258)	(713)
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	(23)	(42)
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	(37)	(65)
Intent to sell	(32)	0
Change in allowance for credit losses on fixed maturity securities	(6)	0
Foreign exchange transactions	(14)	16
Index-linked interest credited embedded derivatives, net of related hedges	0	0
All other derivatives and hedge accounting	(90)	38
Sales of alternative investments and real estate investments	(1)	1
Other	0	0
Net realized gains (losses)	(179)	(31)
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	1	(21)
Fortitude Re funds withheld embedded derivative
Components of net realized capital gains (losses)
Net realized gains (losses)	13	(1,165)
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
Fortitude Re funds withheld embedded derivative \| Fortitude Re Funds Withheld Assets
Components of net realized capital gains (losses)
Net realized gains (losses)	$ 13	$ (1,165)

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).

+ 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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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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