INVENTORIES (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Inventories
Raw coal	$ 40,419	$ 31,689
Saleable coal	57,801	48,522
Supplies	7,326	6,944
Total inventories	$ 105,546	$ 87,155

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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