INVESTMENTS - Information Regarding Pretax Net Gains and Losses From Investments (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	$ (171)	$ 108	$ 224	$ (525)
Credit Losses
Fixed maturity securities available for sale	27	0	38	(75)
Fixed maturity securities held to maturity	0	0	1	1
Commercial mortgage and other loans	(29)	78	15	(86)
Impairment losses	0	0	(20)	0
Loan commitments	3	64	3	(17)
Reinsurance recoverable and other	0	0	(2)	(2)
Total credit losses	1	142	35	(179)
Derivatives and Other
Derivative gains (losses)	(174)	138	(557)	173
Foreign currency gains (losses)	135	(186)	783	(356)
Derivatives and other
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	(39)	(48)	226	(183)
Equity securities
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	(119)	12	(17)	(106)
Fixed maturity securities
Gain (Loss) on Securities [Line Items]
Gross gains from sales	24	7	40	28
Gross losses from sales	(36)	0	(39)	(46)
Foreign currency gains (losses) on sales and redemptions	(2)	(5)	(21)	(39)
Total net investment gains (losses)	$ (14)	$ 2	$ (20)	$ (57)

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

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