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Derivative and Other Financial Instruments - Schedule of Net Fair Values of Outstanding Derivative Contracts and Effect of Hypothetical Change (Increase or Decrease of 10%) in Market Prices or Rates (Detail) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013
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Aluminum Contracts [Member] |
Derivative Instruments, Gain (Loss) [Line Items] |
Fair value asset/(liability) | $ (102)
Index change of + / - 10% | 47
Embedded Credit Derivative [Member] |
Derivative Instruments, Gain (Loss) [Line Items] |
Fair value asset/(liability) | (21)
Index change of + / - 10% | 2
Energy Contracts [Member] |
Derivative Instruments, Gain (Loss) [Line Items] |
Fair value asset/(liability) | 6
Index change of + / - 10% | 214
Foreign Exchange Contracts [Member] |
Derivative Instruments, Gain (Loss) [Line Items] |
Fair value asset/(liability) | (1)
Index change of + / - 10% | 14
Interest Rate Contracts [Member] |
Derivative Instruments, Gain (Loss) [Line Items] |
Fair value asset/(liability) | 29
Index change of + / - 10% | $ 1

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- Definition Index change of plus or minus ten percent in market price or rate. + References No definition available. + Details
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Namespace Prefix: | aa_
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- Definition Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 + Details
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- Details
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