Note 8 - Other Operating Income - Other Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Equity income (loss) - Sunrise Energy	$ (119)	$ (184)	$ 1,167	$ (350)
Government imposition reimbursements	100	150	300	450
Gain on sale of royalty interests in oil properties		0	0	2,949
Coal storage	127	0	211	0
Miscellaneous	266	247	910	2,439
Other Operating Income	$ 374	$ 213	$ 2,588	$ 5,488

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

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