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Decommissioning Liabilities (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Asset Retirement Obligation Disclosure [Line Items] |  |
Estimated reclamation discount rate | 3.30% | 3.00%
Closure cost obligations discount rate | 8.60% | 7.40%
Decommissioning liabilities | $ 193.8 | $ 165.2
Bottom of range |  |
Asset Retirement Obligation Disclosure [Line Items] |  |
Inflation rate | 1.80% | 1.70%
Top of range |  |
Asset Retirement Obligation Disclosure [Line Items] |  |
Inflation rate | 3.70% | 3.60%

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- Definition Closure Cost Obligations Discount Rate + References No definition available. + Details
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- Definition Estimated Reclamation Discount Rate + References No definition available. + Details
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- Details
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- Details
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