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v3.25.1

Share Capital (Share Capital) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2024 | Dec. 31, 2024 | Dec. 31, 2023
Reconciliation of number of shares outstanding [abstract] |  |  |
Beginning balance |  | $ 2,923.5 |
Shares issued through: |  |  |
Shares repurchased and cancelled (in shares) | (451,990) | 0 | 0
Exercise of Manitou warrants (in shares) |  |  | 60,983
Ending balance |  | $ 3,584.2 | $ 2,923.5
Issued capital [member] |  |  |
Reconciliation of number of shares outstanding [abstract] |  |  |
Number of shares outstanding |  | 396,956,984 | 393,806,489
Beginning balance |  | $ 3,738.6 | $ 3,703.8
Shares issued through: |  |  |
Share-based employment compensation plans (in shares) |  | 1,006,149 | 1,425,024
Share-based compensation plans |  | $ 8.6 | $ 12.3
Increase (decrease) through acquisition of subsidiary, equity |  | $ 0.0 | 13.4
Flow-through share financing (in shares) |  | 451,990 |
Flow-through share financing |  | $ 6.5 | $ 0.0
Stock Issued During Period, Share, Acquisition |  | 908,689 |
Dividend reinvestment plan and share purchase plan (in shares) |  | 349,088 | 353,084
Shares issued during period, value, DRIP |  | $ 5.8 | $ 4.1
Shares issued through share purchase plan (in shares) |  | 401,537 | 469,566
ESPP (iv) |  | $ 6.3 | $ 5.6
Exercise of Manitou warrants (in shares) |  | 88,308 |
Exercise of warrants |  | $ 1.4 | 0.9
Cancellation of unexchanged shares |  | $ (2.1) | $ (1.5)
Cancellation of unexchanged shares (in shares) |  | (220,745) | (203,755)
Number of shares outstanding |  | 420,365,051 | 396,956,984
Ending balance |  | $ 4,138.5 | $ 3,738.6
Issued capital [member] | Argonaut Transaction |  |  |
Shares issued through: |  |  |
Shares repurchased and cancelled (in shares) |  | 20,423,051 |
Increase (decrease) through acquisition of subsidiary, equity |  | $ 360.1 |
Issuance of shares related to Argonaut Gold Inc ("Argonaut") acquisition (Note 6) |  | $ 360.1 | $ 0.0
Issued capital [member] | Manitou Gold Inc. |  |  |
Shares issued through: |  |  |
Shares repurchased and cancelled (in shares) |  |  | 1,045,593
Manitou acquisition (Note 9) |  |  | $ 13.4

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