Inventories (Details) - USD ($)	Mar. 31, 2025	Mar. 31, 2024
Inventories
Inventories	$ 2,508,684	$ 2,393,379
Lubricants
Inventories
Inventories	2,309,531	2,184,545
Bonded stores
Inventories
Inventories	$ 199,153	$ 208,834

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://www.xbrl.org/2003/role/exampleRef
-Topic 852
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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