Note 14 - Concentration (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2024	Oct. 31, 2023
Revenue from Contract with Customer, Including Assessed Tax	$ 8,841,000	$ 9,610,000	$ 17,725,000	$ 19,353,000
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| One Single Customer [Member]
Concentration Risk, Percentage			29.70%
Revenue from Contract with Customer, Including Assessed Tax			$ 17,725,000

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.

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+ Details