XML 154 R130.htm IDEA: XBRL DOCUMENT v2.4.1.9

Business Segments Major Customers (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue, Major Customer [Line Items]
Major customer, percentage revenue, net	10.00%us-gaap_ConcentrationRiskPercentage1
Glencore [Member]
Revenue, Major Customer [Line Items]
Major customer, Revenue, net	$ 1,262,101us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_GlencoreMember	$ 511,051us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_GlencoreMember	$ 552,299us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_GlencoreMember
Southwire [Member]
Revenue, Major Customer [Line Items]
Major customer, Revenue, net	226,740us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_SouthwireMember	312,102us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_SouthwireMember	346,311us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_SouthwireMember
RTA [Member]
Revenue, Major Customer [Line Items]
Major customer, Revenue, net	0us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_RTAMember	223,353us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_RTAMember	0us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_RTAMember
BHP Billiton [Member]
Revenue, Major Customer [Line Items]
Major customer, Revenue, net	$ 0us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_BhpBillitonMember	$ 191,445us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_BhpBillitonMember	$ 202,500us-gaap_Revenues / us-gaap_MajorCustomersAxis = cenx_BhpBillitonMember

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

+ Details

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- Details

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Balance Type:	na
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X

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ 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)

-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

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- Details

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- Details

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- Details

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- Details

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