Note 8 - Related-party Transactions (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2018	Apr. 30, 2017
Director David Hayden [Member] \| Consulting Fees [Member]
Related Party Transaction, Amounts of Transaction	$ 135	$ 135
Chief Executive Officer [Member]
Accrued Liabilities, Current, Total	484	389
BHCMC, LLC [Member]
Accounts Receivable, Related Parties, Current	780	780
Wayne Stewart [Member]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	236	225
Craig Stewart [Member]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	330	295
Jeff Shinkle [Member]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	$ 195	$ 188

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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-Name Accounting Standards Codification
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-Section S99
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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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No definition available.

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