Note 4 - Inventories - Summary of Inventory (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Inventories	$ 232,984	$ 163,619
Parts [Member]
Inventories	100,612	92,481
Fuel [Member]
Inventories	117,182	59,336
Other Inventory [Member]
Inventories	$ 15,190	$ 11,802

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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