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Decommissioning Liabilities (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Asset Retirement Obligation Disclosure [Line Items] |  |
Estimated reclamation discount rate | 2.90% | 1.80%
Closure cost obligations discount rate | 10.50% | 10.50%
Decommissioning liability | $ 134.0 | $ 114.9
Bottom of range |  |
Asset Retirement Obligation Disclosure [Line Items] |  |
Inflation rate | 1.90% | 1.90%
Top of range |  |
Asset Retirement Obligation Disclosure [Line Items] |  |
Inflation rate | 9.50% | 9.50%

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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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