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Share Capital (Share Purchase Warrants) (Details) shares in Thousands, $ in Millions | 12 Months Ended
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Dec. 31, 2017 CAD / shares shares | Dec. 31, 2017 USD ($) shares | Dec. 31, 2016 USD ($)
Disclosure of classes of share capital [line items] |  |  |
Number of warrants (in shares) | 12,232 | 12,232 |
Common shares issuable (in shares) | 12,232 | 12,232 |
Gains on derivatives | $ |  | $ 2.3 | $ 1.6
Warrants - Esperanza [Member] |  |  |
Disclosure of classes of share capital [line items] |  |  |
Number of warrants (in shares) | 7,167 | 7,167 |
Common shares issuable (in shares) | 7,167 | 7,167 |
Exercise price (CAD per share) | CAD / shares | CAD 28.46 |  |
Warrants - Carlisle [Member] |  |  |
Disclosure of classes of share capital [line items] |  |  |
Number of warrants (in shares) | 5,065 | 5,065 |
Common shares issuable (in shares) | 5,065 | 5,065 |
Exercise price (CAD per share) | CAD / shares | CAD 10.00 |  |

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- Definition Class of Warrant or Right, Outstanding1 + References No definition available. + Details
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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 gains (losses) resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_85&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Exercise price of the warrants. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column A + Details
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- Details
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