Note 7 - Leases (Details Textual) - USD ($)	9 Months Ended
Feb. 28, 2025	Feb. 29, 2024
Finance Lease, Right-of-Use Asset, Amortization	$ 10,660	$ 21,470
Equipment One [Member]
Finance Lease, Right-of-Use Asset, Amortization	$ 10,660	$ 21,470
Two Buildings [Member]
Lessee, Operating Lease, Term of Contract	120 months
Lessee, Operating Lease, Renewal Term	60 months
Lessee, Operating Lease, Discount Rate	6.00%
Corporate Offices [Member]
Lessee, Operating Lease, Term of Contract	72 months
Lessee, Operating Lease, Discount Rate	8.50%

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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
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-Name Accounting Standards Codification
-Section 55
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

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-SubTopic 20
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- Definition

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

+ References

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-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
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- Definition

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

+ References

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- Details

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- Details

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- Details

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Period Type: