INVESTMENTS - Information Regarding Pretax Realized Gains and Losses From Investments (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses realized	$ (8)	$ (23)	$ (27)	$ (71)
Derivative gains (losses)	(40)	(107)	(143)	(278)
Foreign currency gains (losses)	17	(20)	(56)	(109)
Total realized investment gains (losses)	30	(164)	(166)	(358)
Derivatives and other
Gain (Loss) on Investments [Line Items]
Total realized investment gains (losses)	(23)	(127)	(199)	(387)
Fixed maturities
Gain (Loss) on Investments [Line Items]
Total realized investment gains (losses)	14	(20)	(44)	37
Perpetual securities
Gain (Loss) on Investments [Line Items]
Total realized investment gains (losses)	0	0	4	38
Equity securities
Gain (Loss) on Investments [Line Items]
Gross gains from sales	54	5	102	10
Gross losses from sales	(9)	0	(11)	(10)
Other-than-temporary impairment losses realized	(6)	(22)	(18)	(46)
Total realized investment gains (losses)	39	(17)	73	(46)
Available-for-sale securities \| Fixed maturities
Gain (Loss) on Investments [Line Items]
Gross gains from sales	10	2	27	10
Gross losses from sales	(8)	(22)	(38)	(38)
Net gains (losses) from redemptions	14	1	(24)	88
Other-than-temporary impairment losses realized	(2)	(1)	(9)	(23)
Available-for-sale securities \| Perpetual securities
Gain (Loss) on Investments [Line Items]
Net gains (losses) from redemptions	0	0	4	40
Other-than-temporary impairment losses realized	$ 0	$ 0	$ 0	$ (2)

Gains (losses) from redemptions of securities, net

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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- Definition

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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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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