Note 7 - Income Taxes - Reconciliation of the Federal Statutory Income Tax Rate to the Effective Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2021	Apr. 30, 2020
Statutory federal income tax rate expense, net of noncontrolling interest	21.00%	21.00%
State income tax, net of federal benefits	5.59%	5.10%
Permanent tax	5.36%	1.46%
Other	15.00%	3.60%
Effective Income Tax Rate Reconciliation, Percent, Total	16.95%	23.96%
PROVISION (BENEFIT) FOR INCOME TAXES
Deferred income tax (benefit)	$ (225)	$ (260)
Current Income Tax Expense (Benefit), Total	536	1,594
Total income tax expense	$ 311	$ 1,334