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Forward delivery contracts and financial instruments (Tables) | 3 Months Ended
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Mar. 31, 2012
Forward Delivery Contracts and Financial Instruments [Abstract] |
Schedule of Forward Physical Delivery Agreements | Forward Physical Delivery Agreements Primary Aluminum Sales Contracts
Contract | Customer | Volume | Term | Pricing
Glencore Metal Agreement (1) | Glencore | 20,400 mtpy | Through December 31, 2013 | Variable, based on U.S. Midwest market
Glencore Sweep Agreement (2) | Glencore | Surplus primary aluminum produced in the United States | Through December 31, 2012 | Variable, based on U.S. Midwest market
Glencore Nordural Metal Agreement | Glencore | Approximately 16,000 metric tons | Through December 31, 2012 | Variable, based on LME
Southwire Metal Agreement (3) | Southwire | 240 million pounds per year (high conductivity molten aluminum) | Through December 31, 2013 | Variable, based on U.S. Midwest market
(1) | We account for the Glencore Metal Agreement as a derivative instrument under ASC 815. Under the Glencore Metal Agreement, pricing is based on then-current Midwest market prices, adjusted by a negotiated U.S. Midwest premium with a cap and a floor as applied to the current U.S. Midwest premium.
(2) | The Glencore Sweep Agreement is for all metal produced in the U.S. in 2012, less existing sales agreements and high-purity metal sales. The term of the contract may be extended for one year upon mutual agreement.
(3) | The Southwire Metal Agreement contains termination rights in the event of a partial or full curtailment of the Hawesville facility.
Long-term Tolling Contracts
Contract | Customer | Volume | Term | Pricing
Billiton Tolling Agreement (1) | BHP Billiton | 130,000 mtpy | Through December 31, 2013 | LME-based
Glencore Toll Agreement (1) | Glencore | 90,000 mtpy | Through July 31, 2016 | LME-based
Glencore Toll Agreement (1) | Glencore | 40,000 mtpy | Through December 31, 2014 | LME-based
(1) | Grundartangi’s tolling revenues include a premium based on the European Union (“EU”) import duty for primary aluminum.
Apart from the Glencore Metal Agreement, the Glencore Sweep Agreement, the Glencore Nordural Metal Agreement and the Southwire Metal Agreement, we had the following forward delivery contractual commitments: Other forward delivery contracts
| March 31, 2012 | December 31, 2011
| (in metric tons)
Other forward delivery contracts – total | 63,898 |  | 41,504 |
Other forward delivery contracts – Glencore | 5,219 |  | 3,423 |
Other forward delivery contracts – fixed price | 1,361 |  | 41 |

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- Definition Tabular disclosure of arrangements in which the entity has committed resources to supply goods or services to a customer. May include identification of the goods or services to be furnished, identity of the purchasing party, pricing, effects on pricing for failing to deliver the [minimum] quantities required to be furnished, cancellation rights, and termination provisions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph 25 -SubTopic 10 -Topic 210 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 25 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 17 -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 7 -Section 03 -Paragraph 19 + Details
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