Financial Instruments - Fair Value of Derivatives Segregated Between Those Derivatives That are Designated as Hedging Instruments and Those That are not Designated as Hedging Instruments (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Derivatives, Fair Value [Line Items]
Fair Value of Derivative, Asset	$ 586	$ 755
Fair value of Derivative, Liability	180	108
U.S. Dollar Notional	22,856	20,824
Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Fair Value of Derivative, Asset	513	616
Fair value of Derivative, Liability	55	54
U.S. Dollar Notional	12,181	10,505
Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Fair Value of Derivative, Asset	73	139
Fair value of Derivative, Liability	125	54
U.S. Dollar Notional	10,675	10,319
Foreign exchange contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Deferred income taxes and other current assets [Member]
Derivatives, Fair Value [Line Items]
Fair Value of Derivative, Asset	163	196
U.S. Dollar Notional	4,450	3,727
Foreign exchange contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Fair Value of Derivative, Asset	350	420
U.S. Dollar Notional	5,637	4,956
Foreign exchange contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Accrued And other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of Derivative, Liability	48	53
U.S. Dollar Notional	1,668	1,718
Foreign exchange contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Deferred income taxes and noncurrent liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of Derivative, Liability	7	1
U.S. Dollar Notional	426	104
Foreign exchange contract [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Deferred income taxes and other current assets [Member]
Derivatives, Fair Value [Line Items]
Fair Value of Derivative, Asset	55	139
U.S. Dollar Notional	4,256	5,306
Foreign exchange contract [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Fair Value of Derivative, Asset	18
U.S. Dollar Notional	290
Foreign exchange contract [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Accrued And other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of Derivative, Liability	125	54
U.S. Dollar Notional	$ 6,129	$ 5,013