Note 7 - Long-term Debt - Summary of Long-term Debt (Details) (Parentheticals)	9 Months Ended
Feb. 28, 2026 USD ($)
Revolving loan to International Bank of Commerce [Member]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Term Loan to International Bank of Commerce [Member]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Term Loan to First Interstate Bank [Member]
Debt Instrument, Interest Rate, Stated Percentage	3.50%
Debt Instrument, Periodic Payment	$ 5,997

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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-Name Accounting Standards Codification
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-SubTopic 470
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

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- Details

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