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Note 4 - Other Long-term Assets | 12 Months Ended
--- | ---
Dec. 31, 2020
Notes to Financial Statements |
Other Assets Disclosure [Text Block] | (4) OTHER LONG-TERM ASSETS (IN THOUSANDS)
|  | December 31, |
|  | 2020 |  |  | 2019 |
Advanced coal royalties |  | $ | 6,449 |  |  | $ | 6,105 |
Marketable equity securities available for sale, at fair value (restricted)* |  |  | — |  |  |  | 2,296 |
Other |  |  | 1,809 |  |  |  | 1,923 |
Total other assets |  | $ | 8,258 |  |  | $ | 10,324 |
* Held by Sunrise Indemnity, Inc., our wholly owned captive insurance company.

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- Definition The entire disclosure for other assets. This disclosure includes other current assets and other noncurrent assets. + References No definition available. + Details
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