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Derivatives And Other Financial Instruments (Schedule Of Quantitative Information For Level 3 Derivative Contracts) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended
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Mar. 31, 2012
Discounted Cash Flow [Member] | Embedded Credit Derivative [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Percentage of credit spread | 1.83%
Maximum [Member] | Discounted Cash Flow [Member] | Aluminum Contracts [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Price of aluminum beyond forward curve | 3,057
Maturity data of aluminum beyond forward curve | 2027
Expected future aluminum prices | 2,605
Expected future oil prices | 120
Maximum [Member] | Discounted Cash Flow [Member] | Embedded Credit Derivative [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Percentage of credit spread | 2.02%
Maximum [Member] | Discounted Cash Flow [Member] | Energy Contracts [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Price of electricity beyond forward curve | 172
Maturity date of electricity beyond forward curve | 2036
Minimum [Member] | Discounted Cash Flow [Member] | Aluminum Contracts [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Price of aluminum beyond forward curve | 2,793
Maturity data of aluminum beyond forward curve | 2022
Expected future aluminum prices | 2,152
Expected future oil prices | 91
Minimum [Member] | Discounted Cash Flow [Member] | Embedded Credit Derivative [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Percentage of credit spread | 1.64%
Minimum [Member] | Discounted Cash Flow [Member] | Energy Contracts [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Price of electricity beyond forward curve | 48
Maturity date of electricity beyond forward curve | 2012
Interrelationship Of Future Aluminum And Oil Prices [Member] | Aluminum Contracts [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Derivative Assets, Fair Value | 4
Price Of Aluminum Beyond Forward Curve [Member] | Aluminum Contracts [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Derivative Liabilities, Fair Value | 670
Price Of Electricity Beyond Forward Curve [Member] | Energy Contracts [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Derivative Liabilities, Fair Value | 10
Credit Spread Between Alcoa And Counterparty [Member] | Embedded Credit Derivative [Member] |
Derivatives And Other Financial Instruments [Line Items] |
Derivative Liabilities, Fair Value | 28

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- Details
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- Definition Expected future aluminum prices. + References No definition available. + Details
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- Definition Expected future oil prices. + References No definition available. + Details
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- Definition Maturity data of aluminum beyond forward curve. + References No definition available. + Details
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- Definition Maturity date of electricity beyond forward curve. + References No definition available. + Details
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- Definition Price of electricity through forward curve. + References No definition available. + Details
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- Definition Fair value as of the balance sheet date of the gross assets less the gross liabilities of a derivative asset or group of derivative assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13495-108611 Reference 2: 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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611 + Details
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