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Note 11 - Self-Insurance | 12 Months Ended
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Dec. 31, 2023
Notes to Financial Statements |
Self Insurance [Text Block] | (11) SELF INSURANCE We self-insure non-leased underground mining equipment. Such equipment is allocated among seven mining units dispersed over 11 miles. The historical cost of such equipment was approximately $262 million and $280 million as of December 31, 2023 and 2022, respectively. Restricted cash of $4.3 million and $3.4 million as of December 31, 2023 and 2022, respectively, represents cash held and controlled by a third party and is restricted for future workers’ compensation claim payments.

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