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Share Capital (Flow-though share financing) (Details) - USD ($) $ in Millions |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 01, 2019 | Jun. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Flow-though Share Financing [Line Items] |  |  |  |
Proceeds from issuance of flow-through shares | $ 8.0 |  | $ 7.5 | $ 0.0
CDE and CEE [Member] |  |  |  |
Flow-though Share Financing [Line Items] |  |  |  |
Number of shares issued |  | 1,132,169 |  |
Proceeds from issuance of flow-through shares |  | $ 7.5 |  |

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- Definition [Line Items] for Flow-though Share Financing [Table] + References No definition available. + Details
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- Definition The number of shares issued by the entity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 106 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_106_d&doctype=Standard -URIDate 2019-03-27 + Details
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Period Type: | instant

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- Definition The cash inflow from issuing shares. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 7 -IssueDate 2019-01-01 -Paragraph 17 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_17_a&doctype=Standard -URIDate 2019-03-27 + Details
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- Details
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Period Type: |