INVESTMENTS - Information Regarding Pretax Net Gains and Losses From Investments (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Gain (Loss) on Securities [Line Items]
Gross gains (losses) from sales and redemptions	$ 1	$ 5
Net investment gains (losses)	(963)	951
Credit losses:
Fixed maturity securities held-to-maturity	0	0
Commercial mortgage and other loans	(53)	(7)
Impairment losses	0	0
Loan commitments	(2)	1
Reinsurance recoverables and other	0	5
Total credit losses	(55)	(1)
Derivatives and other:
Derivative gains (losses)	(45)	(215)
Foreign currency gains (losses)	(843)	918
Fixed maturity securities
Gain (Loss) on Securities [Line Items]
Gross gains from sales	114	34
Gross losses from sales	(235)	(282)
Foreign currency gains (losses)	161	416
Debt securities and other investments
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	41	173
Equity securities
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	(61)	76
Derivatives and other
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	$ (888)	$ 703

Foreign currency translation gains (losses) on remeasurement of monetary assets

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Impairment Loss, Investments

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Amount of realized gain 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 expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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