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Derivatives And Other Financial Instruments (Narrative) (Details) | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2011 USD ($) | Jun. 30, 2011 USD ($) | Sep. 30, 2011 USD ($) | Sep. 30, 2011 CAD | Sep. 30, 2011 Level 3 [Member] USD ($) | Jun. 30, 2011 Level 3 [Member] USD ($) | Dec. 31, 2010 Level 3 [Member] USD ($)
Net unrealized loss on derivative contracts |  |  |  |  | $ 574,000,000 | $ 796,000,000 | $ 779,000,000
Number of years of natural gas supply contract | 6 |  |  |  |  |  |
Fair value of natural gas supply contract | 5,000,000 |  | 5,000,000 |  |  |  |
Number of commodities subject to ceiling | 2 |  |  |  |  |  |
Amount of aluminum designated as fair value hedges, kmt |  |  | 310 |  |  |  |
Face amount of debt the hedges effectively convert from fixed to floating through 2018 | 515,000,000 |  | 515,000,000 |  |  |  |
Notional amount interest rate swaps |  | 550,000,000 |  |  |  |  |
Gain on termination of interest rate swaps |  | 33,000,000 |  |  |  |  |
Investment in foreign currency contract, foreign currency amount | $ 56,000,000 |  | $ 56,000,000 | 58,000,000 |  |  |

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- Definition The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16, 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400 + Details
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