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Financial Instruments and Risk Management (Fair Value And Presentation in the Balance Sheet) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of detailed information about financial instruments [line items] |  |
Financial assets, at fair value |  | $ 0.4
Financial liabilities, at fair value | $ (0.1) |
Derivatives [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Financial assets, at fair value |  | 5.0
Financial liabilities, at fair value | (5.2) |
Derivatives [member] | Currency Hedging Derivative Instruments [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Financial assets, at fair value |  | 5.0
Financial liabilities, at fair value | (4.7) |
Derivatives [member] | Fuel Options [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Financial assets, at fair value |  | 0.0
Financial liabilities, at fair value | (0.5) |
Derivatives [member] | Gold Options [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Financial assets, at fair value |  | 0.5
Financial liabilities, at fair value | $ (0.1) |
Derivatives [member] | Share Purchase Warrants [Member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Financial liabilities, at fair value |  | $ (0.1)

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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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- Definition The fair value of financial assets. [Refer: At fair value [member]; Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_25&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The fair value of financial liabilities. [Refer: At fair value [member]; Financial liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_25&doctype=Standard -URIDate 2018-03-16 + Details
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- Details
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- Details
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- Details
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- Details
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