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Note 13 - Self-insurance | 12 Months Ended
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Dec. 31, 2020
Notes to Financial Statements |
Self Insurance [Text Block] | (13) SELF INSURANCE We self-insure our underground mining equipment. Such equipment is allocated among seven mining units dispersed over 10 miles. The historical cost of such equipment was approximately $269 million and $273 million as of December 31, 2020 and December 31, 2019, respectively. Restricted cash of $4.0 million and $4.5 million as of December 31, 2020, and December 31, 2019, respectively, represents cash held and controlled by a third party and is restricted for future workers’ compensation claim payments.

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