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	Jun. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	$ 40,578	$ 38,355
Derivative asset, fair value, gross asset including not subject to master netting arrangement	526	417
Derivative liability, fair value, gross liability including not subject to master netting arrangement	347	387
Asset derivatives fair value	325	234
Liability derivatives fair value	240	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	13,243	11,656
Asset derivatives fair value	0	3
Liability derivatives fair value	24	36
Fair value hedges \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	842	2,086
Asset derivatives fair value	0	0
Liability derivatives fair value	19	34
Fair value hedges \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	10,901	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	3	1
Non-qualifying strategies
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	27,260	26,624
Asset derivatives fair value	526	413
Liability derivatives fair value	317	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	201	181
Liability derivatives fair value	101	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	88	103
Liability derivatives fair value	107	129
Non-qualifying strategies \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	16,081	16,057
Asset derivatives fair value	222	126
Liability derivatives fair value	109	117
Non-qualifying strategies \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net derivatives notional amount	1,042	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	15	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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