Inventories (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Inventory [Line Items] | ||
| Materials and supplies, net | $ 182.2 | $ 161.6 |
| Raw coal | 77.9 | 95.6 |
| Saleable coal | 190.4 | 126.0 |
| Inventories, net | $ 450.5 | $ 383.2 |
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- Definition Raw coal. No definition available.
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- Definition Saleable coal. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed. This amount is net of valuation reserves and adjustments. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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