XML 42 R9.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Long-term power contract for Hawesville | 12 Months Ended
--- | ---
Dec. 31, 2011
Long-term power contract for Hawesville [Abstract] |
Long-term power contract for Hawesville |
2. | Long-term power contract for Hawesville
In July 2009, our wholly owned subsidiary, Century Aluminum of Kentucky (“CAKY”) along with E.ON U.S. (“E.ON”) and Big Rivers Energy Corporation (“Big Rivers” or “BREC”), agreed to an “unwind” of the former contractual arrangement between Big Rivers and E.ON and entered into a new arrangement (“Big Rivers Agreement”) to provide long-term cost-based power to CAKY. The term of the Big Rivers Agreement is through 2023 and provides adequate power for full production capacity requirements for Hawesville (approximately 482 megawatts (“MW”)) with pricing based on the power provider's cost of production. The Big Rivers Agreement is take-or-pay for Hawesville's energy requirements at full production. Under the terms of the agreement, any power not consumed by Hawesville would be available for sale and we would receive credits for actual power sales up to our cost for that power. In connection with the “unwind,” E.ON agreed to mitigate a significant portion of the near-term risk of this agreement through December 2010. During this time, to the extent Hawesville did not use all the power under the take-or-pay contract, E.ON, with some limitations, assumed CAKY's obligations under the former power contract. This effectively resulted in CAKY paying prices which approximated the previous contract prices and volume protection resulting in CAKY receiving credits for unused power without sustaining a loss. Hawesville received these economic benefits during 2009 and 2010. Under the terms of the “unwind,” to the extent the aggregate payments made by E.ON exceeded an agreed upon base amount, CAKY is obligated to repay this excess to E.ON over time under certain conditions. The aggregate balance due to E.ON is recorded in other liabilities. The repayment obligation is contingent upon certain operating criteria and the LME price of primary aluminum. See Note 6 Debt for additional information about the E.ON contingent obligation. During 2011, we paid the full production cost of power under the Big Rivers Agreement. During 2010 and 2009, the full production cost of power was recorded in our cost of goods sold, however we realized benefits of $68,794 and $26,025 for 2010 and 2009, respectively, for E.ON payments made on CAKY's behalf, including amounts incurred for the E.ON contingent obligation. As the previous power contract was designated as a normal contract under ASC 815, in 2009 when it became no longer probable that we would continue to take physical delivery of the power under the previous contract, we recorded a contractual receivable from E.ON representing the net present value of the consideration provided to CAKY from E.ON to net settle the previous contract. We also expensed an intangible asset associated with the former power contract and recorded a $56,964 net gain on this transaction on our consolidated statements of operations in other operating income – net. The new power contract has been designated as a normal purchase contract under ASC 815. The Big Rivers Agreement is a cost-based contract that is not expected to have any significant value and is with a regulated power generator. While the Big Rivers Agreement is a take-or-pay contract, under which we may net settle any unused power with Big Rivers, we would only receive credits up to our cost for such power sales and would not profit on any sales made above our cost for such power under the current election.

X
- Details
Name: | cenx_LongTermPowerContractForHawesvilleAbstract
Namespace Prefix: | cenx_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The entire disclosure for long-term power contract the company has entered with Hawesville. + References No definition available. + Details
Name: | cenx_LongTermPowerContractForHawesvilleTextBlock
Namespace Prefix: | cenx_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration