DERIVATIVE INSTRUMENTS - Summary of Balance Sheet Classification of Derivative Fair Value Amounts, as well as Gross Asset and Liability Fair Value Amounts (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	$ 39,051	$ 38,355
Derivative asset, fair value, gross asset including not subject to master netting arrangement	401	417
Derivative liability, fair value, gross liability including not subject to master netting arrangement	365	387
Asset derivatives fair value	223	234
Liability derivatives fair value	257	285
Cash flow hedges
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	75	75
Asset derivatives fair value	0	1
Liability derivatives fair value	6	4
Cash flow hedges \| Foreign currency swaps \| Variable Interest Entity
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	75	75
Asset derivatives fair value	0	1
Liability derivatives fair value	6	4
Fair value hedges
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	13,079	11,656
Asset derivatives fair value	0	3
Liability derivatives fair value	27	36
Fair value hedges \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	691	2,086
Asset derivatives fair value	0	0
Liability derivatives fair value	24	34
Fair value hedges \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	10,887	9,070
Asset derivatives fair value	0	3
Liability derivatives fair value	2	1
Fair value hedges \| Interest rate swaptions
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	1,500	500
Asset derivatives fair value	0	0
Liability derivatives fair value	1	1
Non-qualifying strategies
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	25,897	26,624
Asset derivatives fair value	401	413
Liability derivatives fair value	332	347
Non-qualifying strategies \| Foreign currency swaps \| Variable Interest Entity
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	2,587	2,587
Asset derivatives fair value	178	181
Liability derivatives fair value	102	101
Non-qualifying strategies \| Foreign currency swaps \| Consolidated Entity Excluding Variable Interest Entities (VIE)
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	2,800	2,800
Asset derivatives fair value	96	103
Liability derivatives fair value	98	129
Non-qualifying strategies \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	15,208	16,057
Asset derivatives fair value	119	126
Liability derivatives fair value	132	117
Non-qualifying strategies \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	552	430
Asset derivatives fair value	0	0
Liability derivatives fair value	0	0
Non-qualifying strategies \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	4,750	4,750
Asset derivatives fair value	8	3
Liability derivatives fair value	$ 0	$ 0

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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