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Note 4 - Other Long-term Assets | 9 Months Ended
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Sep. 30, 2021
Notes to Financial Statements |
Other Assets Disclosure [Text Block] |
(4) | OTHER LONG-TERM ASSETS (in thousands)
|  | September 30, |  |  | December 31, |
|  | 2021 |  |  | 2020 |
Advanced coal royalties |  | $ | 6,705 |  |  | $ | 6,449 |
Other |  |  | 1,723 |  |  |  | 1,809 |
Total other assets |  | $ | 8,428 |  |  | $ | 8,258 |

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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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