Inventories (Details) - USD ($) $ in Thousands |
6 Months Ended | 12 Months Ended |
|---|---|---|
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Inventory [Line Items] | ||
| Coal | $ 37,271 | $ 61,528 |
| Finished goods (net of reserve for obsolescence of $1,733 and $1,133, respectively) | 7,952 | 9,732 |
| Work in process | 169 | 2,660 |
| Raw materials | 8,716 | 6,106 |
| Total operating inventories, net | 54,108 | 80,026 |
| Supplies (net of reserve for obsolescence of $9,998 and $6,901, respectively) | 71,023 | 62,593 |
| Total inventories, net | 125,131 | 142,619 |
| Reduce inventory carrying value to market | 9,700 | 8,300 |
| Manufactured goods | ||
| Inventory [Line Items] | ||
| Reserve for obsolescence | 1,733 | 1,133 |
| Supplies | ||
| Inventory [Line Items] | ||
| Reserve for obsolescence | $ 9,998 | $ 6,901 |
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- Definition Carrying amount as of the balance sheet date of energy and manufactured goods inventory, net of reserves. 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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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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/exampleRef
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of valuation reserve for inventory. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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