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Investments (Net Realized Gains (Losses) And Losses Included In Net Realized Gains (Losses) And Other Comprehensive Income) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2023	Mar. 31, 2022
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Period Increase (Decrease)		$ 59	$ 17
Debt Securities, Available-for-sale, Gain (Loss), Total		(180)	(136)
Net realized gains (losses)		(77)	23
Foreign exchange		131	74
Gain (Loss) on Derivative		(104)	90
Other		(7)	(74)
Fixed Maturities [Member]
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-Sale, Realized Gain (Loss), Excluding Other-than-temporary Impairment		2	39
Debt Securities, Available-for-Sale, Realized Loss, Excluding Other-than-temporary Impairment		(159)	(127)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Period Increase (Decrease)		2	(12)
Debt Securities, Available-For-Sale, Credit Impairment Charges Intent to Sell	[1]	(25)	(36)
Equity Securities
Gain (Loss) on Securities [Line Items]
Equity Securities, FV-NI, Realized Gain (Loss)		11	56
Other Investments
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)		15	55
Other derivative instruments
Gain (Loss) on Securities [Line Items]
Gain (Loss) on Derivative		(1)	1
Investment and embedded derivative instruments
Gain (Loss) on Securities [Line Items]
Gain (Loss) on Derivative		$ (46)	$ 47
[1] Relates to certain securities we intended to sell and securities written to market entering default.

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+ References

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