INVESTMENTS - Information Regarding Pretax Net Gains and Losses From Investments (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Gain (Loss) on Securities [Line Items]
Other investments, gross gains (losses) from sales and redemptions	$ (1)	$ 1	$ (3)	$ 13
Net investment gains (losses)	(1,072)	275	(1,176)	(1,109)
Impairment losses	(1)	0	(36)	(6)
Credit losses:
Fixed maturity securities held to maturity	0	0	(1)	0
Commercial mortgage and other loans	(92)	(51)	(218)	(165)
Loan commitments	(11)	(2)	(10)	(2)
Reinsurance recoverables and other	1	0	(13)	1
Total credit losses	(102)	(53)	(240)	(166)
Derivatives and other:
Derivative gains (losses)	199	(123)	(30)	(145)
Foreign currency gains (losses)	(345)	408	134	(910)
Fixed maturity securities
Gain (Loss) on Securities [Line Items]
Gross gains from sales	5	29	6	148
Gross losses from sales	(925)	(96)	(1,903)	(429)
Foreign currency gains (losses)	79	99	804	339
Debt securities and other investments
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	(842)	33	(1,096)	71
Equity securities
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	19	10	92	47
Derivatives and other
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	$ (146)	$ 285	$ 104	$ (1,055)

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

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