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Segmented Information (Segment revenues and results) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Disclosure of operating segments [line items] |  |
Operating revenues | $ 823.6 | $ 748.1
Cost of sales |  |
Cost of sales | 351.5 | 312.6
Royalties | 11.7 | 10.2
COVID costs |  | 6.5
Amortization | 170.9 | 152.7
Cost of sales | 534.1 | 482.0
Expenses |  |
Exploration | 14.7 | 7.2
Corporate and administrative | 24.5 | 21.0
Share-based compensation | 11.1 | 10.3
Pre-tax impairment charge | 224.3 | 0.0
EARNINGS FROM OPERATIONS | 14.9 | 227.6
Finance costs | (4.5) | (4.3)
Foreign exchange loss | (0.9) | (1.4)
Other loss | (7.2) | (3.7)
EARNINGS BEFORE INCOME TAXES | 2.3 | 218.2
Operating segments [member] | Young-Davidson [Member] |  |
Disclosure of operating segments [line items] |  |
Operating revenues | 350.5 | 239.4
Cost of sales |  |
Cost of sales | 159.7 | 133.9
Royalties | 5.3 | 3.7
COVID costs |  | 0.0
Amortization | 79.4 | 63.7
Cost of sales | 244.4 | 201.3
Expenses |  |
Exploration | 0.7 | 0.0
Corporate and administrative | 0.0 | 0.0
Share-based compensation | 0.0 | 0.0
EARNINGS FROM OPERATIONS | 105.4 | 38.1
Operating segments [member] | Mulatos [Member] |  |
Disclosure of operating segments [line items] |  |
Operating revenues | 221.1 | 261.7
Cost of sales |  |
Cost of sales | 123.1 | 120.9
Royalties | 1.1 | 1.3
COVID costs |  | 2.0
Amortization | 53.2 | 44.6
Cost of sales | 177.4 | 168.8
Expenses |  |
Exploration | 7.3 | 4.2
Corporate and administrative | 0.0 | 0.0
Share-based compensation | 0.0 | 0.0
EARNINGS FROM OPERATIONS | 36.4 | 88.7
Operating segments [member] | Island Gold [Member] |  |
Disclosure of operating segments [line items] |  |
Operating revenues | 252.0 | 247.0
Cost of sales |  |
Cost of sales | 68.7 | 57.8
Royalties | 5.3 | 5.2
COVID costs |  | 4.5
Amortization | 38.3 | 44.4
Cost of sales | 112.3 | 111.9
Expenses |  |
Exploration | 4.7 | 1.0
Corporate and administrative | 0.0 | 0.0
Share-based compensation | 0.0 | 0.0
EARNINGS FROM OPERATIONS | 135.0 | 134.1
Corporate and other [Member] |  |
Disclosure of operating segments [line items] |  |
Operating revenues | 0.0 | 0.0
Cost of sales |  |
Cost of sales | 0.0 | 0.0
Royalties | 0.0 | 0.0
COVID costs |  | 0.0
Amortization | 0.0 | 0.0
Cost of sales | 0.0 | 0.0
Expenses |  |
Exploration | 2.0 | 2.0
Corporate and administrative | 24.5 | 21.0
Share-based compensation | 11.1 | 10.3
Pre-tax impairment charge | 224.3 |
EARNINGS FROM OPERATIONS | $ (261.9) | $ (33.3)

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