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Segmented Information (Segment revenues and results) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Disclosure of operating segments [line items] |  |
Operating revenues | $ 1,346.9 | $ 1,023.3
Cost of sales |  |
Mining and processing | 518.9 | 437.3
Royalties | 13.8 | 10.2
Amortization | 218.4 | 190.2
Cost of sales | 751.1 | 637.7
Expenses |  |
Exploration | 26.7 | 18.2
Corporate and administrative | 32.6 | 27.6
Share-based compensation | 31.7 | 21.7
Reversal of impairment (Note 9) | (57.1) | 0.0
EARNINGS FROM OPERATIONS | 561.9 | 318.1
Finance expense (Note 19) | (3.8) | (2.5)
Foreign exchange gain | 8.0 | 1.9
Unrealized loss on commodity derivatives | (24.2) | (0.9)
Other loss | (39.7) | (22.9)
EARNINGS BEFORE INCOME TAXES | 502.2 | 293.7
Young-Davidson |  |
Expenses |  |
Reversal of impairment (Note 9) | (57.1) |
Corporate/Other |  |
Expenses |  |
Exploration | 4.9 |
Corporate and administrative | 32.6 |
Share-based compensation | 31.7 |
EARNINGS FROM OPERATIONS | (69.2) |
Operating segments | Young-Davidson |  |
Disclosure of operating segments [line items] |  |
Operating revenues | 415.3 | 355.3
Cost of sales |  |
Mining and processing | 178.4 | 166.2
Royalties | 6.2 | 5.3
Amortization | 77.3 | 76.7
Cost of sales | 261.9 | 248.2
Expenses |  |
Exploration | 3.0 | 2.9
EARNINGS FROM OPERATIONS | 207.5 | 104.2
Operating segments | Island Gold |  |
Disclosure of operating segments [line items] |  |
Operating revenues | 363.1 | 247.8
Cost of sales |  |
Mining and processing | 87.7 | 82.7
Royalties | 3.2 | 2.7
Amortization | 41.3 | 38.2
Cost of sales | 132.2 | 123.6
Expenses |  |
Exploration | 5.0 | 3.7
EARNINGS FROM OPERATIONS | 225.9 | 120.5
Operating segments | Magino |  |
Disclosure of operating segments [line items] |  |
Operating revenues | 81.2 |
Cost of sales |  |
Mining and processing | 55.8 |
Royalties | 2.0 |
Amortization | 16.1 |
Cost of sales | 73.9 |
Expenses |  |
Exploration | 0.7 |
EARNINGS FROM OPERATIONS | 6.6 |
Operating segments | Mulatos |  |
Disclosure of operating segments [line items] |  |
Operating revenues | 487.3 | 420.2
Cost of sales |  |
Mining and processing | 197.0 | 188.4
Royalties | 2.4 | 2.2
Amortization | 83.7 | 75.3
Cost of sales | 283.1 | 265.9
Expenses |  |
Exploration | 13.1 | 9.9
EARNINGS FROM OPERATIONS | $ 191.1 | 144.4
Operating segments | Corporate/Other |  |
Expenses |  |
Exploration |  | 1.7
Corporate and administrative |  | 27.6
Share-based compensation |  | 21.7
EARNINGS FROM OPERATIONS |  | $ (51.0)

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