Note 15 - Equity Method Investments	12 Months Ended
Dec. 31, 2021
Notes to Financial Statements
Equity Method Investments and Joint Ventures Disclosure [Text Block]	(15) EQUITY METHOD INVESTMENTS Sunrise Energy, LLC We own a 50% interest in Sunrise Energy, LLC, which owns gas reserves and gathering equipment with plans to develop and operate such reserves. Sunrise Energy also plans to develop and explore for oil, gas, and coal-bed methane gas reserves on or near our underground coal reserves. The carrying value of the investment included in our consolidated balance sheets as of December 31, 2021 and 2020 was $3.5 million and $3.2 million, respectively. Sunrise Energy plans to develop and explore for oil, gas, and coal-bed methane gas reserves on or near our underground coal reserves.

The entire disclosure for equity method investments and joint ventures. Equity method investments are investments that give the investor the ability to exercise significant influence over the operating and financial policies of an investee. Joint ventures are entities owned and operated by a small group of businesses as a separate and specific business or project for the mutual benefit of the members of the group.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-URI http://asc.fasb.org/topic&trid=2196965

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