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, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	$ 28,803	$ 25,751
Derivative asset, fair value, gross asset including not subject to master netting arrangement	457	331
Derivative liability, fair value, gross liability including not subject to master netting arrangement	(367)	(474)
Asset derivatives fair value	255	180
Liability derivatives fair value	(276)	(346)
Other assets
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	17,559	10,948
Asset derivatives fair value	457	331
Liability derivatives fair value	0	0
Other liabilities
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	11,244	14,803
Asset derivatives fair value	0	0
Liability derivatives fair value	(367)	(474)
Cash flow hedges
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	75	75
Asset derivatives fair value	1	0
Liability derivatives fair value	(4)	(8)
Cash flow hedges \| Foreign currency swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	75	75
Asset derivatives fair value	1	0
Liability derivatives fair value	(4)	(8)
Fair value hedges
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	12,535	15,310
Asset derivatives fair value	17	2
Liability derivatives fair value	(8)	(223)
Fair value hedges \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	3,310	7,640
Asset derivatives fair value	17	2
Liability derivatives fair value	(3)	(221)
Fair value hedges \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	9,225	7,670
Asset derivatives fair value	0	0
Liability derivatives fair value	(5)	(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	16,193	9,927
Asset derivatives fair value	439	317
Liability derivatives fair value	(355)	(242)
Non-qualifying strategies \| Foreign currency swaps
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	5,390	5,386
Asset derivatives fair value	320	296
Liability derivatives fair value	(223)	(189)
Non-qualifying strategies \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	10,410	3,683
Asset derivatives fair value	119	20
Liability derivatives fair value	(132)	(53)
Non-qualifying strategies \| Foreign currency options
Derivatives, Fair Value [Line Items]
Net Derivatives Notional Amount	303	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	90	88
Asset derivatives fair value	0	1
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
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