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Financial Instruments and Risk Management (Credit Risk) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of detailed information about financial instruments [line items] |  |
Total financial instrument exposure to credit risk | $ 214.0 | $ 208.0
Cash and Cash Equivalents [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Total financial instrument exposure to credit risk | 206.0 | 200.8
Concentrate Receivable [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Total financial instrument exposure to credit risk | 2.3 | 3.2
Trade receivables [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Total financial instrument exposure to credit risk | $ 5.7 | $ 4.0

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- Definition The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 35K -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_35K_a&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2021-01-01 -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 36 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_36_a&doctype=Standard&book=b -URIDate 2018-03-16 + Details
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- Details
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- Details
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- Details
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