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Asset Retirement Obligations (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2023 | Dec. 31, 2024 | Dec. 31, 2022
Segment Reporting Information [Line Items] |  |  |
Cash received | $ 2.2 |  |
Estimated asset retirement obligation | 1.9 |  |
Gain on the assumption of third-party asset retirement obligation | $ 0.3 |  |
Marshall Mine |  |  |
Segment Reporting Information [Line Items] |  |  |
Membership interest (percent) | 100.00% |  |
Bellaire |  |  |
Segment Reporting Information [Line Items] |  |  |
Initial investment amount |  |  | $ 5.0
Fair value of trust assets | $ 11.2 | $ 12.3 |

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- Definition Asset Retirement Obligation, Legally Restricted Assets, Initial Investment Amount + References No definition available. + Details
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- Definition Fair Market Value Of The Asset Retirement Obligation Assumed From A Third-Party + References No definition available. + Details
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- Definition Gain On The Assumption Of Third-Party Asset Retirement Obligation + References No definition available. + Details
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- Definition Carrying amount of an asset that is legally restricted for purposes of settling an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481850/410-20-50-1 + Details
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- Details
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- Details
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