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Related party transactions (Tables) | 9 Months Ended
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Sep. 30, 2017
Related Party Transactions [Abstract] |
Schedule of related party transactions | A summary of the aforementioned significant related party transactions for the three and nine months ended September 30, 2017 and 2016 is as follows:
| Three months ended September 30, |  | Nine months ended September 30,
| 2017 |  | 2016 |  | 2017 |  | 2016
Net sales to Glencore | $ | 299,235 |  |  | $ | 301,111 |  |  | $ | 876,079 |  |  | $ | 871,771 |
Purchases from Glencore | 81,905 |  |  | 62,317 |  |  | 195,073 |  |  | 156,507 |
Purchases from BHH | 3,248 |  |  | 2,568 |  |  | 9,137 |  |  | 7,666 |

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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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