INVESTMENTS - Information Regarding Pretax Realized Gains and Losses From Investments (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Gain (Loss) on Securities [Line Items]
Loan loss reserves	$ (5)	$ (5)	$ (8)	$ (15)
Derivative gains (losses)	(146)	(162)	(24)	(190)
Foreign currency gains (losses)	21	159	(181)	123
Total realized investment gains (losses)	(153)	56	(147)	(76)
Loan receivables
Gain (Loss) on Securities [Line Items]
Total realized investment gains (losses)	(5)	(5)	(8)	(15)
Derivatives and other
Gain (Loss) on Securities [Line Items]
Total realized investment gains (losses)	(125)	(3)	(205)	(67)
Equity securities
Gain (Loss) on Securities [Line Items]
Total realized investment gains (losses)	18	27	65	(1)
Available-for-sale securities \| Fixed maturities
Gain (Loss) on Securities [Line Items]
Gross gains from sales	11	60	55	81
Gross losses from sales	(18)	(26)	(29)	(99)
Foreign currency gains (losses) on sales and redemptions	(21)	3	(12)	27
Other-than-temporary impairment losses realized	(13)	0	(13)	(2)
Total realized investment gains (losses)	$ (41)	$ 37	$ 1	$ 7

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

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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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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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