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v3.19.1

Summary of significant accounting policies - Narrative (Details) - Mobile Equipment, Tailings Dam and Equipment | 12 Months Ended
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Dec. 31, 2018
Bottom of range |
Disclosure of detailed information about property, plant and equipment [line items] |
Useful lives of property, plant and equipment | 3 years
Top of range |
Disclosure of detailed information about property, plant and equipment [line items] |
Useful lives of property, plant and equipment | 6 years

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- Definition Useful Lives Or Depreciation Rates, Property, Plant And Equipment, Period + References No definition available. + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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