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Income Taxes (Schedule of Tax Losses Expiry Dates) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Income Taxes [line items] |  |
Unused tax losses for which no deferred tax asset recognised | $ 72,156 | $ 81,188
CANADA |  |
Income Taxes [line items] |  |
Unused tax losses for which no deferred tax asset recognised | $ 84,200 | $ 81,000
CANADA | Bottom of range [member] |  |
Income Taxes [line items] |  |
Year of Expiry | 2026 | 2026
CANADA | Top of range [member] |  |
Income Taxes [line items] |  |
Year of Expiry | 2039 | 2038
ARGENTINA |  |
Income Taxes [line items] |  |
Unused tax losses for which no deferred tax asset recognised | $ 42,500 | $ 11,900
ARGENTINA | Bottom of range [member] |  |
Income Taxes [line items] |  |
Year of Expiry | 2020 | 2019
ARGENTINA | Top of range [member] |  |
Income Taxes [line items] |  |
Year of Expiry | 2024 | 2023
MEXICO |  |
Income Taxes [line items] |  |
Unused tax losses for which no deferred tax asset recognised | $ 369 | $ 349
MEXICO | Bottom of range [member] |  |
Income Taxes [line items] |  |
Year of Expiry | 2021 | 2021
MEXICO | Top of range [member] |  |
Income Taxes [line items] |  |
Year of Expiry | 2029 | 2028
PERU |  |
Income Taxes [line items] |  |
Year of Expiry | 2021 | 2021
Unused tax losses for which no deferred tax asset recognised | $ 70 | $ 238

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- Definition The amount of unused tax losses for which no deferred tax asset is recognised in the statement of financial position. [Refer: Unused tax losses [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2018-01-01 -Paragraph 81 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2018-03-01&anchor=para_81_e&doctype=Standard -URIDate 2018-03-16 + Details
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