Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	$ (281)	$ (252)	$ (847)	$ (908)
Impairment (losses)	(591)	(3)	(1,496)	(38)
Change in allowance for credit loss recognized in earnings	25	72	(199)	(87)
Unrealized net gains (losses) recognized in earnings	(17)	(44)	37	(102)
Total recognized gains (losses)	8	28	(162)	(189)
Non-investment portfolio gains (losses)	(63)	(184)	(145)	(475)
Net investment gains (losses)	(927)	(411)	(2,650)	(1,610)
Impairment (losses)	(444)	$ (3)	(1,300)	$ (38)
Reinsurance Risk Transfer Transaction
Gain (Loss) on Securities [Line Items]
Impairment (losses)	(438)		(1,300)
Commercial Mortgage Loans \| Reinsurance Risk Transfer Transaction
Gain (Loss) on Securities [Line Items]
Other Asset Impairment Charges	$ 12		$ 56

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

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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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Amount of unrealized gain (loss) on investment.

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