Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	$ (1,028)	$ (880)	$ 711
Impairment (losses)	(1,498)	(40)	(24)
Change in allowance for credit loss recognized in earnings	(271)	(134)	(86)
Unrealized net gains (losses) recognized in earnings	54	(100)	227
Total recognized gains (losses)	(217)	(234)	141
Non-investment portfolio gains (losses)	(81)	(106)	715
Net investment gains (losses)	(2,824)	(1,260)	1,543
Gain (Loss) on Sale of Mortgage Loans	(2)
Impairment (losses)	(1,300)	(40)	(24)
Fixed maturity securities AFS (1)	(2,471)	$ (1,912)	$ 66
Reinsurance Risk Transfer Transaction
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	1,200
Impairment (losses)	(1,300)
Fixed maturity securities AFS (1)	95
Commercial Mortgage Loans \| Reinsurance Risk Transfer Transaction
Gain (Loss) on Securities [Line Items]
Other Asset Impairment Charges	$ (56)

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Gain (Loss) Recognized in Earnings

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Amount of unrealized and 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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Amount of realized and unrealized gain (loss) on investment.

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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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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Amount of unrealized gain (loss) on investment.

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