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Related party transactions (Tables) | 6 Months Ended
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Jun. 30, 2017
Related Party Transactions [Abstract] |
Schedule of related party transactions | A summary of the aforementioned significant related party transactions for the three and six months ended June 30, 2017 and 2016 is as follows:
| Three months ended June 30, |  | Six months ended June 30,
| 2017 |  | 2016 |  | 2017 |  | 2016
Net sales to Glencore | $ | 296,271 |  |  | $ | 290,283 |  |  | $ | 576,844 |  |  | $ | 570,660 |
Purchases from Glencore | 41,587 |  |  | 50,177 |  |  | 113,168 |  |  | 94,190 |
Purchases from BHH | 3,109 |  |  | 2,715 |  |  | 5,889 |  |  | 5,098 |

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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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