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v3.24.1

Financial Instruments and Risk Management (Fair Value for Assets and Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Disclosure of fair value measurement of assets [line items] |  |
Milestone payments | $ 5.7 | $ 19.1
Asset held for sale | 0.0 | 5.0
Total liabilities | 1,077.7 | 953.1
Total Assets | 4,001.2 | 3,674.2
Derivative assets (note 17) | 6.6 | 0.0
Derivative liabilities (note 20) | 1.0 | 4.2
Derivatives | Gold Options |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial liabilities, at fair value | (0.8) |
Derivatives | Currency Hedging Derivative Instruments |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial liabilities, at fair value | 6.6 |
Derivatives | Fuel Options |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial assets, at fair value | (0.2) |
Level 3 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Milestone payments |  | 19.1
Asset held for sale | 0.0 | 5.0
Fair value, net asset (liability) | 5.7 | 24.1
Level 2 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Fair value, net asset (liability) | 5.2 | (4.2)
Level 2 | Recurring fair value measurement | Fair value through profit or loss | Gold Options |  |
Disclosure of fair value measurement of assets [line items] |  |
Total liabilities |  | 0.1
Level 2 | Recurring fair value measurement | Fair value through profit or loss | Share Purchase Warrants |  |
Disclosure of fair value measurement of assets [line items] |  |
Financial liabilities, at fair value | (0.4) |
Level 2 | Recurring fair value measurement | Fair value through OCI | Currency Hedging Derivative Instruments |  |
Disclosure of fair value measurement of assets [line items] |  |
Total liabilities |  | (4.3)
Level 1 | Recurring fair value measurement |  |
Disclosure of fair value measurement of assets [line items] |  |
Fair value, net asset (liability) | 13.0 | 18.6
Level 1 | Recurring fair value measurement | Trading securities | Fair value through OCI |  |
Disclosure of fair value measurement of assets [line items] |  |
Total Assets | $ 13.0 | $ 18.6

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