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Ravenswood property sale (Details) $ in Thousands | 1 Months Ended
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Jan. 31, 2017 USD ($)
Ravenswood Aluminum Smelter [Member] |
Impaired Assets to be Disposed of by Method Other than Sale [Line Items] |
Proceeds from sale of Ravenswood facility and assets | $ 15,000

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- Definition The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 + Details
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- Details
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