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Mineral Property, Pland and Equipment (Net Value Carrying Values) (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | $ 2,933.4 | $ 2,813.3
Plant and Equipment [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 856.8 | 796.5
Mineral Property - Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 1,720.7 | 1,681.6
Mineral Property - Non-Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 99.8 | 90.7
Exploration and evaluation assets [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 256.1 | 244.5
Operating segments [member] | Young-Davidson [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 1,467.4 | 1,444.3
Operating segments [member] | Young-Davidson [Member] | Plant and Equipment [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 658.0 | 608.9
Operating segments [member] | Young-Davidson [Member] | Mineral Property - Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 709.6 | 744.7
Operating segments [member] | Young-Davidson [Member] | Mineral Property - Non-Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 99.8 | 90.7
Operating segments [member] | Young-Davidson [Member] | Exploration and evaluation assets [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments [member] | Mulatos [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 244.0 | 209.4
Operating segments [member] | Mulatos [Member] | Plant and Equipment [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 82.6 | 101.0
Operating segments [member] | Mulatos [Member] | Mineral Property - Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 161.4 | 108.4
Operating segments [member] | Mulatos [Member] | Mineral Property - Non-Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments [member] | Mulatos [Member] | Exploration and evaluation assets [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments [member] | Island Gold [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 824.3 | 800.1
Operating segments [member] | Island Gold [Member] | Plant and Equipment [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 108.9 | 79.5
Operating segments [member] | Island Gold [Member] | Mineral Property - Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 715.4 | 720.6
Operating segments [member] | Island Gold [Member] | Mineral Property - Non-Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments [member] | Island Gold [Member] | Exploration and evaluation assets [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments [member] | El Chanate [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.2 | 2.3
Operating segments [member] | El Chanate [Member] | Plant and Equipment [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.2 | 1.5
Operating segments [member] | El Chanate [Member] | Mineral Property - Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.8
Operating segments [member] | El Chanate [Member] | Mineral Property - Non-Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments [member] | El Chanate [Member] | Exploration and evaluation assets [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments [member] | Kirazli Segment [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 134.6 | 107.4
Operating segments [member] | Kirazli Segment [Member] | Plant and Equipment [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.3 | 0.3
Operating segments [member] | Kirazli Segment [Member] | Mineral Property - Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 134.3 | 107.1
Operating segments [member] | Kirazli Segment [Member] | Mineral Property - Non-Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments [member] | Kirazli Segment [Member] | Exploration and evaluation assets [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Corporate and other [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 262.9 | 249.8
Corporate and other [Member] | Plant and Equipment [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 6.8 | 5.3
Corporate and other [Member] | Mineral Property - Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Corporate and other [Member] | Mineral Property - Non-Depletable [Member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Corporate and other [Member] | Exploration and evaluation assets [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | $ 256.1 | $ 244.5

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- Definition The amount of tangible assets that: (a) are held for use in the production or supply of goods or services, for rental to others, or for administrative purposes; and (b) are expected to be used during more than one period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2019-01-01 -Paragraph 73 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 54 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_54_a&doctype=Standard -URIDate 2019-03-27 + Details
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