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	Sep. 30, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	$ 31,023	$ 25,751
Derivative asset, fair value, gross asset including not subject to master netting arrangement	430	331
Derivative liability, fair value, gross liability including not subject to master netting arrangement	(497)	(474)
Asset derivatives fair value	240	180
Liability derivatives fair value	(396)	(346)
Other assets
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	11,232	10,948
Asset derivatives fair value	430	331
Liability derivatives fair value	0	0
Other liabilities
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	19,791	14,803
Asset derivatives fair value	0	0
Liability derivatives fair value	(497)	(474)
Cash flow hedges
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	75	75
Asset derivatives fair value	0	0
Liability derivatives fair value	(5)	(8)
Cash flow hedges \| Foreign currency swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	75	75
Asset derivatives fair value	0	0
Liability derivatives fair value	(5)	(8)
Fair value hedges
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	12,451	15,310
Asset derivatives fair value	0	2
Liability derivatives fair value	(79)	(223)
Fair value hedges \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	3,172	7,640
Asset derivatives fair value	0	2
Liability derivatives fair value	(67)	(221)
Fair value hedges \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	9,279	7,670
Asset derivatives fair value	0	0
Liability derivatives fair value	(12)	(2)
Net investment hedge
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	0	439
Asset derivatives fair value	0	12
Liability derivatives fair value	0	(1)
Net investment hedge \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	0	5
Asset derivatives fair value	0	0
Liability derivatives fair value	0	0
Net investment hedge \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	0	434
Asset derivatives fair value	0	12
Liability derivatives fair value	0	(1)
Non-qualifying strategies
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	18,497	9,927
Asset derivatives fair value	430	317
Liability derivatives fair value	(413)	(242)
Non-qualifying strategies \| Foreign currency swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	5,373	5,386
Asset derivatives fair value	302	296
Liability derivatives fair value	(202)	(189)
Non-qualifying strategies \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	10,501	3,683
Asset derivatives fair value	128	20
Liability derivatives fair value	(210)	(53)
Non-qualifying strategies \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	373	770
Asset derivatives fair value	0	0
Liability derivatives fair value	0	0
Non-qualifying strategies \| Credit default swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	0	88
Asset derivatives fair value	0	1
Liability derivatives fair value	0	0
Non-qualifying strategies \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	2,250	0
Asset derivatives fair value	0	0
Liability derivatives fair value	$ (1)	$ 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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