Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Realized gains (losses) on investments sold or disposed	$ (546)	$ (211)
Impairment (losses)	(7)	(40)
Change in allowance for credit loss recognized in earnings	(182)	(243)
Unrealized net gains (losses) recognized in earnings	38	(15)
Total recognized gains (losses)	(144)	(258)
Non-investment portfolio gains (losses)	13	(8)
Net investment gains (losses)	$ (684)	$ (517)

Change in allowance for credit loss recognized in earnings

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Gain (Loss) Recognized in Earnings

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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 realized gain (loss) on investment.

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Amount of unrealized gain (loss) on investment.

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