INVESTMENTS - Information Regarding Pretax Net Gains and Losses From Investments (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	$ 89	$ (170)	$ 396	$ (633)
Credit Losses
Fixed maturity securities available for sale	0	(12)	11	(75)
Fixed maturity securities held to maturity	0	0	1	1
Commercial mortgage and other loans	17	(127)	44	(164)
Impairment losses	0	0	(20)	0
Loan commitments	(5)	(35)	0	(81)
Reinsurance recoverable and other	0	(2)	(2)	(2)
Total credit losses	12	(176)	34	(321)
Derivatives and Other
Derivative gains (losses)	(96)	120	(383)	35
Foreign currency gains (losses)	(3)	(93)	648	(170)
Derivatives and other
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	(99)	27	265	(135)
Equity securities
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	170	31	102	(118)
Fixed maturity securities
Gain (Loss) on Securities [Line Items]
Gross gains from sales	14	14	16	21
Gross losses from sales	(2)	(46)	(3)	(46)
Foreign currency gains (losses) on sales and redemptions	(6)	(20)	(18)	(34)
Total net investment gains (losses)	$ 6	$ (52)	$ (5)	$ (59)

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

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