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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	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

Income Taxes [line items].

+ References

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- Definition

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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

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