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INCOME AND MINING TAXES (Details Textual) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income and mining taxes [Line Items] |  |  |
Applicable tax rate |  | 26.30% | 25.80%
Unused tax credits for which no deferred tax asset recognised |  | $ 196.6 | $ 240.9
Temporary differences associated with investments in subsidiaries, branches and associates and interests in joint arrangements for which deferred tax liabilities have not been recognised |  | 123.2 | 114.6
Increase (decrease) in deferred tax liability (asset) |  | $ 2.0 | $ 1.2
Tax rate effect from change in tax rate |  | 11.50% | 12.00%
Other temporary differences [member] |  |  |
Income and mining taxes [Line Items] |  |  |
Unused tax losses for which no deferred tax asset recognised |  | $ 20.4 |
U.S. Federal Corporate Tax Rate [Member] |  |  |
Income and mining taxes [Line Items] |  |  |
Increase (decrease) in deferred tax liability (asset) |  | $ 32.6 |
Scenario, Plan [Member] |  |  |
Income and mining taxes [Line Items] |  |  |
Applicable tax rate | 21.00% | 35.00% |
Canada [Member] | Unused Capital Losses [Member] |  |  |
Income and mining taxes [Line Items] |  |  |
Unused Capital Losses For Which No Deferred Tax Assets Recognized |  | $ 41.3 |
Canada [Member] | Unused tax losses [member] |  |  |
Income and mining taxes [Line Items] |  |  |
Unused tax losses for which no deferred tax asset recognised |  | $ 0.6 |
Canada [Member] | Bottom of range [member] | Unused tax losses [member] |  |  |
Income and mining taxes [Line Items] |  |  |
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits |  | 2018 |
Canada [Member] | Top of range [member] | Unused tax losses [member] |  |  |
Income and mining taxes [Line Items] |  |  |
Description of expiry date of deductible temporary differences, unused tax losses and unused tax credits |  | 2036 |

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- Definition The applicable income tax rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_c_ii&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The tax rate effect on the reconciliation between the average effective tax rate and the applicable tax rate resulting from a change in tax rate. [Refer: Average effective tax rate; Applicable tax rate] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_c_ii&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The aggregate amount of temporary differences associated with investments in subsidiaries, branches and associates and interests in joint arrangements, for which deferred tax liabilities have not been recognised as a result of satisfying both of the following conditions: (a) the parent, investor, joint venturer or joint operator is able to control the timing of the reversal of the temporary difference; and (b) it is probable that the temporary difference will not reverse in the foreseeable future. [Refer: Associates [member]; Subsidiaries [member]; Temporary differences [member]; Investments in subsidiaries] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_f&doctype=Standard -URIDate 2017-03-09 + Details
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