Note 12 - Major Customers (Details Textual)	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Lion Oil Trading and Transportation, LLC [Member]
Concentration Risk, Percentage	88.00%	95.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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