Inventories (Narrative) (Details) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
|
| Inventories [Line Items] | ||
| Cost of inventories recognised as expense during period | $ 1,243.4 | $ 1,288.4 |
| Write-downs (recovery) of cost of sales | 4.1 | 2.9 |
| Manitoba [Member] | ||
| Inventories [Line Items] | ||
| Cost of inventories recognised as expense during period | 25.6 | |
| Peru [Member] | ||
| Inventories [Line Items] | ||
| Cost of inventories recognised as expense during period | 13.0 | |
| Copper concentrate and stockpile inventory [Member] | ||
| Inventories [Line Items] | ||
| Write-downs (recovery) of cost of sales | 0.0 | 0.2 |
| Non-current inventory supplies [Member] | ||
| Inventories [Line Items] | ||
| Write-downs (recovery) of cost of sales | $ 4.1 | $ 2.7 |