XML 43 R40.htm IDEA: XBRL DOCUMENT v2.4.1.9

Related party transactions (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Related Party Transaction [Line Items]
Related parties	$ 575,729us-gaap_RevenueFromRelatedParties	$ 285,583us-gaap_RevenueFromRelatedParties
Glencore [Member]
Related Party Transaction [Line Items]
Related parties	575,729us-gaap_RevenueFromRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cenx_GlencoreMember	285,583us-gaap_RevenueFromRelatedParties / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cenx_GlencoreMember
Purchases from Glencore	107,814us-gaap_RelatedPartyCosts / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cenx_GlencoreMember	63,857us-gaap_RelatedPartyCosts / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cenx_GlencoreMember
BHH [Member]
Related Party Transaction [Line Items]
Purchases from BHH	$ 14,820cenx_PurchasesFromBhh / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cenx_BhhMember	$ 14,607cenx_PurchasesFromBhh / us-gaap_RelatedPartyTransactionsByRelatedPartyAxis = cenx_BhhMember
BHH [Member]
Related Party Transaction [Line Items]
Equity Method Investment, Ownership Percentage	40.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = cenx_BhhMember

X

- Definition

Direct costs arising from transactions with related parties who are joint ventures. These costs are categorized as cost of goods sold

+ References

No definition available.

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X

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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X

- Definition

Direct costs arising from transactions with related parties who are not affiliates or joint Ventures. These costs are categorized as cost of goods sold.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(k)(1))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph k

-Subparagraph 1

-Article 4



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Related Parties

-URI http://asc.fasb.org/extlink&oid=16382449



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-07.1(c))

-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 07

-Paragraph b

-Subparagraph 1

-Article 6

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- Details

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