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Commitments and contingencies (Details) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2014 LaborUnions MW
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OR Power Purchase Agreement Abstract] |
Power currently available under the power purchase agreement (in megawatts) | 47.5 cenx_PowerAvailable
Power prepayments | $ 2,062 us-gaap_PrepaidExpenseNoncurrent
Labor Commitments [Abstract] |
Percentage of Company's work force represented by a union (in hundredths) | 59.00%cenx_PercentageofWorkForceinUnion
Percentage of Grundartangi work force represented by the labor unions (in hundredths) | 81.00%cenx_PercentageOfForeignWorkForceCoveredUnderNewLaborAgreement
Number of Labor Unions Under New Labor Agreement (in number of unions) | 5 cenx_NumberOfLaborUnionsUnderNewLaborAgreement
Percentage of Vlissingen work force represented by the labor union (in hundredths) | 80.00%cenx_PercentageofforeignNetherlandsworkforcerepresentedbythelaborunioninhundredths
Percentage of U.S. based work force represented by a union (in hundredths) | 54.00%cenx_PercentageOfDomesticWorkForceInUnion

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- Details
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- Details
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- Definition The number of labor unions representing a group of employees. + References No definition available. + Details
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- Definition The percentage of a Company's work force, based in the country of domicile, that are subject to collective bargaining agreements. + References No definition available. + Details
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- Definition The percentage of a Company's Netherlands work force that are subject to collective bargaining agreements + References No definition available. + Details
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Namespace Prefix: | cenx_
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Balance Type: | na
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- Definition The percentage of a Company's Icelandic work force that are subject to collective bargaining agreements. + References No definition available. + Details
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- Definition The percentage of a Company's work force that are subject to collective bargaining agreements. + References No definition available. + Details
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Namespace Prefix: | cenx_
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Balance Type: | na
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- Definition The power currently available under the power purchase agreement. + References No definition available. + Details
Name: | cenx_PowerAvailable
Namespace Prefix: | cenx_
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Balance Type: | na
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- Definition Sum of the carrying amounts as of the balance sheet date of amounts paid in advance for expenses which will be charged against earnings in periods after one year or beyond the operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 + Details
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