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Derivatives and Other Financial Instruments - Schedule of Gain or Loss on Hedged Items and Derivative Contracts (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of gain/loss recognized in earnings related to the ineffective portion of hedging relationships | $ (1) | $ (1) | $ 3
Sales [Member] | Aluminum Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of gain/loss recognized in earnings related to the ineffective portion of hedging relationships | $ 1 | $ (18) | $ 7

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- Definition Derivative instruments gain loss recognized in income related to ineffective portion. + References No definition available. + Details
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- Details
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