Note 8 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2022	Apr. 30, 2021
Current Income Tax Expense (Benefit), Total	$ 3,102	$ 536
Current Federal Tax Expense (Benefit)	2,279	328
Current State and Local Tax Expense (Benefit)	$ 823	208
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total		$ 0

Amount of current federal tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current national tax expense (benefit) for non-US (United States of America) jurisdiction.

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Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

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Amount of current state and local tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current regional, territorial, and provincial tax expense (benefit) for non-US (United States of America) jurisdiction.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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