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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Taxes [line items] |  |  |  |
Applicable tax rate |  |  | 26.00% | 26.00%
PERU | Changes in tax rates or tax laws enacted or announced [member] |  |  |  |
Income Taxes [line items] |  |  |  |
Applicable tax rate |  | 29.50% |  |
ARGENTINA |  |  |  |
Income Taxes [line items] |  |  |  |
Applicable tax rate |  |  | 35.00% |
ARGENTINA | Changes in tax rates or tax laws enacted or announced [member] |  |  |  |
Income Taxes [line items] |  |  |  |
Applicable tax rate | 25.00% | 30.00% |  |
British Columbia [member] |  |  |  |
Income Taxes [line items] |  |  |  |
Applicable tax rate |  |  | 11.00% |
British Columbia [member] | Changes in tax rates or tax laws enacted or announced [member] |  |  |  |
Income Taxes [line items] |  |  |  |
Applicable tax rate |  | 12.00% |  |
CANADA |  |  |  |
Income Taxes [line items] |  |  |  |
Resource related expense accumulated with no deferred tax benefit recognized |  |  | $ 5,773 | $ 3,271
CANADA | Changes in tax rates or tax laws enacted or announced [member] |  |  |  |
Income Taxes [line items] |  |  |  |
Applicable tax rate |  | 27.00% |  |

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- Definition The applicable income tax rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_c_ii&doctype=Standard -URIDate 2017-03-09 + Details
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