Impact of Derivative Instruments in Consolidated Balance Sheet (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012		Dec. 31, 2011
Derivative [Line Items]
Derivative assets	$ 7		$ 6
Derivative liabilities	33		68
Designated as Hedging Instrument
Derivative [Line Items]
Derivative assets	5		0
Derivative liabilities	30		63
Designated as Hedging Instrument | Foreign Exchange Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative assets	5	[1]	0
Derivative liabilities	30	[2]	53	[3]
Other current assets | Designated as Hedging Instrument | Foreign Exchange Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative assets	3
Deferred charges and other assets | Designated as Hedging Instrument | Foreign Exchange Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative assets	2
Other Accrued Liabilities | Designated as Hedging Instrument | Foreign Exchange Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative liabilities	25		32
Other Liabilities | Designated as Hedging Instrument | Foreign Exchange Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative liabilities	$ 5		$ 21

[1] Includes $3 million in Other current assets and $2 million in Deferred charges and other assets in the accompanying consolidated balance sheet.

[2] Includes $25 million recorded in Other accrued liabilities and $5 million recorded in Other liabilities in the accompanying consolidated balance sheet.

[3] Includes $32 million recorded in Other accrued liabilities and $21 million recorded in Other liabilities in the accompanying consolidated balance sheet.