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Related party transactions (Tables) | 3 Months Ended
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Mar. 31, 2018
Related Party Transactions [Abstract] |
Schedule of related party transactions | A summary of the aforementioned significant related party transactions is as follows:
| Three months ended March 31,
| 2018 |  | 2017
Net sales to Glencore | $ | 296.2 |  |  | $ | 280.6 |
Purchases from Glencore | 48.4 |  |  | 71.6 |
Purchases from BHH | 7.4 |  |  | 2.8 |

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- References No definition available. + Details
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- Definition Tabular disclosure of related party transactions. Examples of related party transactions include, but are not limited to, transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners and (d) affiliates. + References No definition available. + Details
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