Fair Value of Derivative Instruments (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 179	$ 312
Liability Derivatives	825	278
Derivatives Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives	15	144
Liability Derivatives	509	49
Derivatives Designated as Hedging Instruments \| Currency exchange contracts
Derivatives, Fair Value [Line Items]
Asset Derivatives	0	19
Liability Derivatives	0	8
Derivatives Designated as Hedging Instruments \| Commodity contracts
Derivatives, Fair Value [Line Items]
Asset Derivatives	0	17
Liability Derivatives	0	22
Derivatives Designated as Hedging Instruments \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Asset Derivatives	15	108
Liability Derivatives	509	19
Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives	164	168
Liability Derivatives	316	229
Derivatives Not Designated as Hedging Instruments \| Currency exchange contracts
Derivatives, Fair Value [Line Items]
Asset Derivatives	65	29
Liability Derivatives	76	43
Derivatives Not Designated as Hedging Instruments \| Commodity contracts
Derivatives, Fair Value [Line Items]
Asset Derivatives	84	112
Liability Derivatives	229	167
Derivatives Not Designated as Hedging Instruments \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Asset Derivatives	15	27
Liability Derivatives	$ 11	$ 19

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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- Definition

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