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Production costs by nature (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Disclosure Of Expense By Nature [Line Items] |  |
Raw materials and consumables | $ 310,534 | $ 184,746
Contractors | 80,884 | 63,328
Salaries and employee benefits | 122,782 | 74,010
Electricity | 19,476 | 18,652
Equipment rental | 4,733 | 6,987
Other | 30,347 | 21,767
Silver credits | (5,092) | (7,850)
Change in inventories | (13,001) | (26,140)
Capitalized to mining interests | (74,961) | (33,106)
Total Production Expense | 475,702 | 302,394
General And Administrative Costs |  |
Disclosure Of Expense By Nature [Line Items] |  |
Salaries and employee benefits | $ 30,000 | $ 22,000

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- Definition The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 102 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_102&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 99 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_99&doctype=Standard -URIDate 2017-03-09 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 104 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_104&doctype=Standard -URIDate 2017-03-09 + Details
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