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Derivatives And Other Financial Instruments (Schedule Of Outstanding Forward Contracts That Were Entered Into Hedge Forecasted Transactions) (Details) | Mar. 31, 2012 | Dec. 31, 2011
--- | --- | ---
Derivative Instruments, Gain (Loss) [Line Items] |  |
Natural gas (million British thermal units) | 18,540,000 |
Energy Contracts [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Energy contracts (electricity-megawatt hours) | 100,578,295 | 100,578,295
Aluminum Contracts [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Aluminum contracts (kmt) | 1,342 | 1,294

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- Definition Outstanding Forward Contracts Entered Into As Hedge Forecasted Transactions Measured In British Thermal Units + References No definition available. + Details
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- Definition Outstanding forward contracts entered into as hedge forecasted transactions measured in mega watt hours. + References No definition available. + Details
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- Definition Outstanding forward contracts entered into as hedging forecasted transactions measured in kilo metric ton. + References No definition available. + Details
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- Details
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