INVESTMENTS - Information Regarding Pretax Net Gains and Losses From Investments (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	$ 307	$ (463)
Credit Losses
Fixed maturity securities available for sale	11	(63)
Fixed maturity securities held to maturity	1	1
Commercial mortgage and other loans	27	(37)
Impairment losses	(20)	0
Loan commitments	5	(46)
Reinsurance recoverable and other	(2)	0
Total credit losses	22	(145)
Derivatives and Other
Derivative gains (losses)	(287)	(85)
Foreign currency gains (losses)	651	(77)
Derivatives and other
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	364	(162)
Equity securities
Gain (Loss) on Securities [Line Items]
Total net investment gains (losses)	(68)	(149)
Fixed maturity securities
Gain (Loss) on Securities [Line Items]
Gross gains from sales	2	7
Gross losses from sales	(1)	0
Foreign currency gains (losses) on sales and redemptions	(12)	(14)
Total net investment gains (losses)	$ (11)	$ (7)

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

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Amount of increase (decrease) in allowance for credit loss of 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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