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Acquisition of Argonaut Gold, Inc. (Schedule of Asset Acquisition) (Details) $ in Millions |  |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jul. 12, 2024 USD ($) $ / oz $ / shares oz $ / shares | Apr. 04, 2024 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) $ / oz | Dec. 31, 2024 USD ($) $ / shares | Dec. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) $ / shares | Jul. 15, 2024 oz | Jun. 12, 2024 USD ($)
Net assets acquired |  |  |  |  |  |  |  |  |
Deferred tax asset |  |  |  | $ 61.2 | $ 61.2 | $ 0.0 | $ 0.0 |  |
Share price (cad per share) | $ / shares |  |  |  |  | $ 26.52 |  | $ 17.74 |  |
Borrowings |  |  |  | 250.0 | $ 250.0 | 0.0 | $ 0.0 |  |
Repayments of borrowings |  |  | $ 308.3 | $ 308.3 |  | $ 0.0 |  |  |
Average realized price per ounce | $ / oz |  |  |  | 1,950 |  |  |  |  |
Forward contract |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Ounces subject to contract | oz | 329,417 |  |  |  |  |  |  |  |
Ounces subject to contract, settled | oz |  |  |  |  |  |  |  | 179,417 |
Forward contract | Bottom of range |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Average realized price per ounce | $ / oz | 1,821 |  |  |  |  |  |  |  |
Forward contract | Top of range |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Average realized price per ounce | $ / oz | 1,860 |  |  |  |  |  |  |  |
Revolving Credit Facility |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Borrowings | $ 218.0 |  |  | $ 250.0 | 250.0 |  |  |  |
Convertible Debentures |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Borrowings | 57.5 |  |  |  |  |  |  |  |
Obligation Prepayment |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Borrowings | $ 24.2 |  |  |  |  |  |  |  |
Florida Canyon Gold |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Percentage of voting equity interests acquired | 19.90% |  |  |  |  |  |  |  |
Argonaut Transaction |  |  |  |  |  |  |  |  |
Consideration transferred |  |  |  |  |  |  |  |  |
Fair value of total shares issued as of acquisition date |  |  |  |  |  |  |  |  | $ 360.1
Fair value of interest prior to acquisition date |  |  |  |  |  |  |  |  | 58.9
Total consideration |  |  |  |  |  |  |  |  | $ 419.0
Net assets acquired |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  |  |  | 6.7 | 6.7 |  |  |  |
Receivables and other assets |  |  |  | 6.2 | 6.2 |  |  |  |
Inventories |  |  |  | 38.6 | 38.6 |  |  |  |
Mineral properties and plant and equipment |  |  |  | 683.2 | 683.2 |  |  |  |
Deferred tax asset |  |  |  | 61.2 | 61.2 |  |  |  |
Accrued liabilities and other liabilities |  |  |  | 88.7 | 88.7 |  |  |  |
Debt |  |  |  | (299.7) | (299.7) |  |  |  |
Other long term liabilities |  |  |  | (4.6) | (4.6) |  |  |  |
Derivative hedge liabilities |  |  |  | (226.0) | (226.0) |  |  |  |
Lease liabilities |  |  |  | (47.2) | (47.2) |  |  |  |
Decommissioning liability |  |  |  | (18.0) | (18.0) |  |  |  |
Identifiable assets acquired (liabilities assumed) |  |  |  | 419.0 | 419.0 |  |  |  |
Share price (cad per share) | $ / shares | $ 0.51 |  |  |  |  |  |  |  |
Closing foreign exchange rate | $ / shares | 1.3616 |  |  |  |  |  |  |  |
Right-of-use assets | $ 47.2 |  |  |  |  |  |  |  |
Repayments of borrowings |  |  |  | 299.7 |  |  |  |  |
Argonaut Transaction | Mineral Property, Plant and Equipment |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Mineral properties and plant and equipment |  |  |  | $ 307.3 | $ 307.3 |  |  |  |
Argonaut Transaction | Argonaut |  |  |  |  |  |  |  |  |
Consideration transferred |  |  |  |  |  |  |  |  |
Total consideration |  | $ 58.9 |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Proportion of ownership interests held by non-controlling interests | 13.80% | 13.80% |  |  |  |  |  |  |
Argonaut Transaction | Florida Canyon Gold |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Percentage of voting equity interests acquired | 19.99% |  |  |  |  |  |  |  |
Argonaut Transaction | Ordinary shares |  |  |  |  |  |  |  |  |
Net assets acquired |  |  |  |  |  |  |  |  |
Share price (cad per share) | $ / shares | $ 24.02 |  |  |  |  |  |  |  |
Closing foreign exchange rate | $ / shares | 1.3616 |  |  |  |  |  |  |  |

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