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Note 8 - Other Operating Income (Tables) | 12 Months Ended
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Dec. 31, 2020
Notes Tables |
Schedule of Other Operating Income (Expense) [Table Text Block] |
|  | Year Ended December 31, |
|  | 2020 |  |  | 2019 |
Equity income (loss) - Sunrise Energy |  | $ | 1,054 |  |  | $ | (527 | )
MSHA reimbursements |  |  | 400 |  |  |  | 575 |
Gain on sale of royalty interests in oil properties |  |  | — |  |  |  | 2,949 |
Miscellaneous |  |  | 1,757 |  |  |  | 3,029 |
|  | $ | 3,211 |  |  | $ | 6,026 |

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- References No definition available. + Details
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