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Contingencies And Commitments (Litigation) (Narrative) (Details) (USD $) In Millions, unless otherwise specified |  |  | 1 Months Ended | 12 Months Ended | 0 Months Ended |
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Nov. 08, 2011 days | May 31, 2011 Breaches Of Warranty [Member] | Nov. 30, 2006 Curtis V. Alcoa Inc. [Member] days | Dec. 31, 2011 SCRG, Brownfield Recovery Corp., Energy Answers Corporation Of Puerto Rico [Member] | Jan. 20, 2011 SCRG, Brownfield Recovery Corp., Energy Answers Corporation Of Puerto Rico [Member] Breaches Of Warranty [Member] | Jan. 20, 2011 SCRG, Brownfield Recovery Corp., Energy Answers Corporation Of Puerto Rico [Member] Punitive Damages [Member] | Jan. 20, 2011 SCRG, Brownfield Recovery Corp., Energy Answers Corporation Of Puerto Rico [Member] Property Damages [Member] | Feb. 27, 2008 Aluminium Bahrain B.S.C. V. Alcoa Inc. [Member] years
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Period of alleged conspiracy, years |  |  |  |  |  |  |  | 15
Number of days required to dismiss lawsuit | 30 |  |  |  |  |  |  |
Retired former employees involved in class action |  |  | 13,000 |  |  |  |  |
Trial length, number of days |  |  | 8 |  |  |  |  |
Damages awarded to plaintiff |  |  |  |  | $ 13 | $ 6 | $ 10 |
Post-trial litigation charge recorded |  |  |  | 20 |  |  |  |
Damages awarded to plaintiff, pre-judgment interest |  | $ 2 |  |  |  |  |  |

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- Definition Damages awarded to plaintiff, pre-judgment interest. + References No definition available. + Details
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- Details
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