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General Retrospective Adjustment (Policies) | 6 Months Ended
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Jun. 30, 2014
Retrospective Adjustment [Abstract] |
Retrospective adjustment policy | In the second quarter of 2013, we acquired the Sebree smelter and reported provisional amounts for the assets acquired and the liabilities assumed in our Form 10-Q for the period ended June 30, 2013. See Note 2 Acquisition of Sebree aluminum smelter for additional information. In accordance with Financial Accounting Standards Board ("FASB") Accounting Standards Codification ("ASC") 805 "Business Combinations," we retrospectively adjusted our 2013 interim consolidated financial statements for certain measurement period adjustments for the items acquired in the acquisition and the financial results for 2013 presented in this Form 10-Q reflect these adjustments.

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- Definition Disclosure of accounting policy for reclassifications that affects the comparability of the financial statements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6359566&loc=d3e326-107755 + Details
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