XML 43 R76.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Property, Plant, and Equipment Property, Plant, and Equipment (Detail Textual) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Property, Plant and Equipment [Line Items] |  |  |
Property, plant and equipment — net | $ 1,291,218 us-gaap_PropertyPlantAndEquipmentNet | $ 1,247,661 us-gaap_PropertyPlantAndEquipmentNet |
Construction in progress | 182,393 us-gaap_ConstructionInProgressGross | 221,101 us-gaap_ConstructionInProgressGross |
Depreciation | 70,731 us-gaap_Depreciation | 66,570 us-gaap_Depreciation | 62,570 us-gaap_Depreciation
Mt. Holly Property, plant and equipment, gross |  | 179,702 cenx_EquityMethodInvestmentOwnershipInPropertyPlantAndEquipment |
Mt. Holly Property Property, plant and equipment, accumulated depreciation |  | 119,275 cenx_EquityMethodInvestmentOwnershipInPropertyPlantAndEquipmentAccumulatedDepreciation |
Ravenswood Aluminum Smelter [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Property, plant and equipment — net | 45,683 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cenx_RavenswoodAluminumSmelterMember |  |
Helguvik Project [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Construction in progress | $ 147,587 us-gaap_ConstructionInProgressGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = cenx_HelguvikProjectMember |  |

X
- Definition Represents the entity's equity undivided ownership interest in property, plant and equipment in Mt. Holly partnership. + References No definition available. + Details
Name: | cenx_EquityMethodInvestmentOwnershipInPropertyPlantAndEquipment
Namespace Prefix: | cenx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Represents the accumulated depreciation on entity's equity undivided ownership interest in property, plant and equipment in Mt. Holly partnership. + References No definition available. + Details
Name: | cenx_EquityMethodInvestmentOwnershipInPropertyPlantAndEquipmentAccumulatedDepreciation
Namespace Prefix: | cenx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
Name: | us-gaap_ConstructionInProgressGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 + Details
Name: | us-gaap_Depreciation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph a -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 7 + Details
Name: | us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=cenx_HelguvikProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=cenx_RavenswoodAluminumSmelterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |