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Long-term power contract for Hawesville (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Long-term power contract for Hawesville [Abstract] |  |  |
Term of the Big Rivers Agreement | through 2023 |  |
Adequate power provided for full production capacity requirements (in megawatts) | 482 |  |
Realized benefit of contractual receivable |  | $ 68,794 | $ 26,025
Net gain on long-term power delivery contract termination |  |  | $ 56,964

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- Details
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- Definition The electrical power requirements necessary for full production requirement. + References No definition available. + Details
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- Definition This element represents the income received from or payment made to a third party in connection with the contract receivable between the parties. + References No definition available. + Details
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- Definition This element represent the expiration date of the contract. + References No definition available. + Details
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- Definition Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 + Details
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