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v3.19.1

Segmented Information (Segment assets and liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Disclosure of operating segments [line items] |  |
Total Assets | $ 3,265.2 | $ 3,320.3
Total liabilities | 662.9 | 639.1
Operating segments [member] | Young-Davidson [Member] |  |
Disclosure of operating segments [line items] |  |
Total Assets | 1,569.4 | 1,580.9
Total liabilities | 272.3 | 243.4
Operating segments [member] | Mulatos [Member] |  |
Disclosure of operating segments [line items] |  |
Total Assets | 366.9 | 356.5
Total liabilities | 95.4 | 100.3
Operating segments [member] | Island Gold [Member] |  |
Disclosure of operating segments [line items] |  |
Total Assets | 876.2 | 849.6
Total liabilities | 236.3 | 222.5
Operating segments [member] | El Chanate [Member] |  |
Disclosure of operating segments [line items] |  |
Total Assets | 35.9 | 111.4
Total liabilities | 5.9 | 24.3
Corporate and other [Member] |  |
Disclosure of operating segments [line items] |  |
Total Assets | 416.8 | 421.9
Total liabilities | $ 53.0 | $ 48.6

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