Location on the Balance Sheet of Derivative Assets and Liabilities (Detail) (Fair Value, Inputs, Level 2, USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Asset Derivatives
Asset Derivatives	$ 325	$ 347
Derivative Asset, Fair Value, Net	248	242
Derivative Liabilities [Abstract]
Liability Derivatives	116	121
Derivative Liability, Fair Value, Amount Offset Against Collateral	(39)	(16)
Designated as Hedging Instrument | Foreign Exchange Contracts | Other current assets
Asset Derivatives
Asset Derivatives	14	10
Derivative Asset, Fair Value, Net	11	4
Designated as Hedging Instrument | Foreign Exchange Contracts | Other noncurrent assets
Asset Derivatives
Asset Derivatives	36	59
Derivative Asset, Fair Value, Net	36	59
Designated as Hedging Instrument | Foreign Exchange Contracts | Other current liabilities
Derivative Liabilities [Abstract]
Liability Derivatives	(6)	(6)
Derivative Liability, Fair Value, Amount Offset Against Collateral	3	0
Designated as Hedging Instrument | Foreign Exchange Contracts | Other non-current liabilities
Derivative Liabilities [Abstract]
Liability Derivatives	23	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	(23)	0
Designated as Hedging Instrument | Interest Rate Contracts | Other current assets
Asset Derivatives
Asset Derivatives	0	7
Derivative Asset, Fair Value, Net	0	7
Designated as Hedging Instrument | Interest Rate Contracts | Other noncurrent assets
Asset Derivatives
Asset Derivatives	211	204
Derivative Asset, Fair Value, Net	141	110
Designated as Hedging Instrument | Interest Rate Contracts | Other non-current liabilities
Derivative Liabilities [Abstract]
Liability Derivatives	76	104
Derivative Liability, Fair Value, Amount Offset Against Collateral	(6)	(10)
Not Designated as Hedging Instrument | Foreign Exchange Contracts | Other current assets
Asset Derivatives
Asset Derivatives	6	7
Derivative Asset, Fair Value, Net	5	5
Not Designated as Hedging Instrument | Foreign Exchange Contracts | Other current liabilities
Derivative Liabilities [Abstract]
Liability Derivatives	(8)	(7)
Derivative Liability, Fair Value, Amount Offset Against Collateral	7	5
Not Designated as Hedging Instrument | Interest Rate Contracts | Other noncurrent assets
Asset Derivatives
Asset Derivatives	58	60
Derivative Asset, Fair Value, Net	55	57
Not Designated as Hedging Instrument | Interest Rate Contracts | Other current liabilities
Derivative Liabilities [Abstract]
Liability Derivatives	0	1
Derivative Liability, Fair Value, Amount Offset Against Collateral	0	(1)
Not Designated as Hedging Instrument | Interest Rate Contracts | Other non-current liabilities
Derivative Liabilities [Abstract]
Liability Derivatives	3	3
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 0	$ 0