Note 7 - Leases (Details Textual) - USD ($)	9 Months Ended
Feb. 29, 2024	Feb. 28, 2023	May 31, 2023
Property, Plant and Equipment, Net	$ 30,594,286		$ 33,184,706
Finance Lease, Right-of-Use Asset, Amortization	21,470	$ 189,927
Equipment One [Member]
Property, Plant and Equipment, Net	63,457
Finance Lease, Right-of-Use Asset, Amortization	$ 21,470	$ 189,927
Lessee, Operating Lease, Term of Contract (Month)	52 months
Lessee, Operating Lease, Discount Rate	5.40%
Equipment Two [Member]
Lessee, Operating Lease, Term of Contract (Month)	48 months
Lessee, Operating Lease, Discount Rate	5.40%
Two Buildings [Member]
Lessee, Operating Lease, Discount Rate	6.00%

Amount of amortization expense attributable to right-of-use asset from finance lease.

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Discount rate used by lessee to determine present value of operating lease payments.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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