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v3.19.1

Decommissioning Liabilities (Details) - Provision for decommissioning, restoration and rehabilitation costs [member] - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Reconciliation of changes in other provisions [abstract] |  |
Beginning balance | $ 44.6 | $ 39.6
Liability assumed on acquisition |  | 2.4
Reclamation, Care and Maintenance Expenses | 0.9 | 0.1
Accretion expense | 3.0 | 2.6
Revisions to expected discounted cash flows | (1.8) | 0.1
Ending balance | $ 44.9 | $ 44.6

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- Definition Reclamation Expenses + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition The increase (decrease) in other provisions resulting from a change in discount rate. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2018-01-01 -Paragraph 84 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2018-03-01&anchor=para_84_e&doctype=Standard -URIDate 2018-03-16 + Details
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Period Type: | duration

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- Definition The increase in other provisions through adjustments arising from the passage of time. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2018-01-01 -Paragraph 84 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2018-03-01&anchor=para_84_e&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of provisions other than provisions for employee benefits. [Refer: Provisions] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2018-01-01 -Paragraph 84 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2018-03-01&anchor=para_84_a&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 78 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_78_d&doctype=Standard -URIDate 2018-03-16 + Details
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Balance Type: | credit
Period Type: | instant

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- Definition The amount used (ie incurrent and charged against the provision) for other provisions. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2018-01-01 -Paragraph 84 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2018-03-01&anchor=para_84_c&doctype=Standard -URIDate 2018-03-16 + Details
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- References No definition available. + Details
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- Details
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