Note 16 - Concentration (Details Textual) - USD ($)	12 Months Ended
Apr. 30, 2026	Apr. 30, 2025	Apr. 30, 2024
Revenue from Contract with Customer, Including Assessed Tax	$ 33,447,000	$ 35,079,000	$ 37,487,000
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| One Single Customer [Member]
Concentration Risk, Percentage	28.70%	29.60%	32.20%
Revenue from Contract with Customer, Including Assessed Tax	$ 33,447,000	$ 35,079,000	$ 37,487,000

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-40

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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+ Details