Note 8 - Other Operating Income - Other Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Equity income (loss) - Sunrise Energy	$ 1,231	$ (132)	$ 1,286	$ (166)
Government imposition reimbursements	100	150	200	300
Gain on sale of royalty interests in oil properties	0	449	0	2,949
Coal storage	84	0	84	0
Miscellaneous	193	730	644	2,192
Other Operating Income	$ 1,608	$ 1,197	$ 2,214	$ 5,275

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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