Inventories - Schedule of Components of Inventories (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Inventory Disclosure [Abstract] | ||
| Coal | $ 100.8 | $ 116.5 |
| Coke | 20.7 | 39.7 |
| Materials, supplies and other | 64.6 | 63.7 |
| Total inventories | $ 186.1 | $ 219.9 |
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- Definition Coke. No definition available.
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- Definition Materials, supplies and other. No definition available.
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- Definition Carrying amount as of the balance sheet date of coal, which is a combustible rock or minerals which are extracted from the ground and used as fuel. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References 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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