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Business acquisitions Acquisition of Mt. Holly aluminum smelter additional (Details) (Mt. Holly Smelter [Member]) | Dec. 01, 2014 t
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Mt. Holly Smelter [Member] |
Business Acquisition [Line Items] |
Percentage of voting interests acquired (percentage) | 50.30%us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeIncludingSubsequentAcquisitionPercentage / us-gaap_BusinessAcquisitionAxis = cenx_Mt.HollySmelterMember
Percentage of ownership after acquisition (percentage) | 100.00%cenx_BusinessAcquisitionPercentageofOwnershipAfterAcquisition / us-gaap_BusinessAcquisitionAxis = cenx_Mt.HollySmelterMember
Employees | 600 dei_EntityNumberOfEmployees / us-gaap_BusinessAcquisitionAxis = cenx_Mt.HollySmelterMember
Primary aluminum capacity (in tonnes) | 231,000 cenx_Primaryaluminumcapacity / us-gaap_BusinessAcquisitionAxis = cenx_Mt.HollySmelterMember
Equity interest in acquiree (percentage) | 49.70%us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireePercentage / us-gaap_BusinessAcquisitionAxis = cenx_Mt.HollySmelterMember

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- Definition Percentage of ownership at the acquisition date as a result of the business combination. + References No definition available. + Details
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- Definition Annual production capacity of primary aluminum (in tonnes). + References No definition available. + Details
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X
- Definition Number of persons employed by the Entity + References No definition available. + Details
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X
- Details
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X
- Definition Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date. + References No definition available. + Details
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X
- Definition Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination. + References No definition available. + Details
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