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Noncontrolling Interests (Tables) | 12 Months Ended
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Dec. 31, 2011
Noncontrolling Interests [Abstract] |
Schedule Of Noncontrolling Shareholders' Interests |
December 31, |  | 2011 |  |  | 2010 |
Alcoa World Alumina and Chemicals |  | $ | 3,324 |  |  | $ | 3,452 |
Other |  |  | 27 |  |  |  | 23 |
|  | $ | 3,351 |  |  | $ | 3,475 |

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- Definition Schedule of Noncontrolling Shareholders Interests[Text Block] + References No definition available. + Details
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- Details
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