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Provisions and contingent liabilities (Details 2) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of provisions [Line Items] |  |  |
Changes in estimates, Note 7 | $ 32,000 |  |
Provision for remediation and mine closure [Member] |  |  |
Disclosure of provisions [Line Items] |  |  |
Beginning balance | 156,859 | $ 153,313 | $ 161,270
Accretion expense | 4,322 | 4,595 | 4,391
Changes in estimates, Note 7 | (32,017) | (3,710) | (16,091)
Additions, Note 7 | 2,724 | 2,661 | 3,743
Final balance | $ 131,888 | $ 156,859 | $ 153,313

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- Definition The amount of additional other provisions made. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2018-01-01 -Paragraph 84 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2018-03-01&anchor=para_84_b&doctype=Standard -URIDate 2018-03-16 + Details
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