Note 3 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2018	Apr. 30, 2017
Current Income Tax Expense (Benefit), Total	$ (192)	$ 589
Current Federal Tax Expense (Benefit)	(295)	550
Current State and Local Tax Expense (Benefit)	103	$ 39
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	$ 0

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

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