Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed (1)	$ (135)	$ (546)
Impairment (losses)	0	(7)
Change in allowance for credit loss recognized in earnings	(46)	(182)
Unrealized net gains (losses) recognized in earnings	32	38
Total recognized gains (losses)	(14)	(144)
Non-investment portfolio gains (losses)	(226)	13
Net investment gains (losses)	(375)	(684)
Impairment (losses)	0	$ (7)
Private Equity Funds
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed (1)	43
Equity Method Investment, Amount Sold	741
Proceeds from Sale of Equity Method Investments	$ 698

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Gain (Loss) Recognized in Earnings

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Amount of the entity's equity method investment which has been sold.

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

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Amount of gain (loss) on sale or disposal of other assets.

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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 other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Amount of unrealized gain (loss) on investment.

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