Segment Information (Narrative) (Details) - segment |
3 Months Ended | |
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Mar. 31, 2018 |
Mar. 31, 2017 |
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| Concentration Risk [Line Items] | ||
| Number of reportable operating segments | 2 | |
| Sales Revenue, Net [Member] | Glencore U.K. [Member] | Gabon Segment [Member] | ||
| Concentration Risk [Line Items] | ||
| Concentration Risk, Percentage | 100.00% | 100.00% |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. No definition available.
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