Related parties (Narrative) (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Apr. 30, 2025 |
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| Disclosure of transactions between related parties [line items] | |||
| Interest expense | $ 60.7 | $ 69.8 | |
| Unrealized foreign exchange gains (losses) on intra-group loan balances | 21.6 | (24.5) | |
| Mitsubishi Materials Corporation [Member] | |||
| Disclosure of transactions between related parties [line items] | |||
| Revenue from sale of goods | 78.0 | 274.1 | |
| Outstanding trade receivables | $ 0.0 | 45.3 | |
| Interest expense | $ 0.9 | ||
| Mitsubishi Materials Corporation [Member] | Copper Mountain Mine (BC) Ltd. [Member] | |||
| Disclosure of transactions between related parties [line items] | |||
| Percentage of voting equity interests acquired | 25.00% | ||
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- Definition Represents amount of unrealized foreign exchange gains (losses) on intra-group loan balances. No definition available.
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- Definition The amounts receivable resulting from related party transactions. [Refer: Total for all related parties [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. No definition available.
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- Definition The amount of expense arising from interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The percentage of voting equity interests acquired in a business combination. [Refer: Total for all business combinations [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References Reference 1: http://www.xbrl.org/2003/role/exampleRef
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