Note 14 - Equity Method Investments	12 Months Ended
Dec. 31, 2023
Notes to Financial Statements
Equity Method Investments and Joint Ventures Disclosure [Text Block]	(14) EQUITY METHOD INVESTMENTS Sunrise Energy, LLC We own a 50% interest in Sunrise Energy, 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, natural gas, and coal-bed methane gas reserves on or near our underground coal reserves. The carrying value of the investment included in the consolidated balance sheets as of December 31, 2023 and 2022 was $2.8 million and $4.0 million, respectively.

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
-Topic 323
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-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
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Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 323
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481543/323-740-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
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