INCOME TAXES - Statutory Rate Reconciliation (Details) - USD ($)	12 Months Ended
	Apr. 30, 2019	Apr. 30, 2018
Income Tax Reconciliation
Computed tax expense at statutory rates	$ 137,000	$ (405,000)
Permanent differences	6,000	11,000
State tax and credits	56,000	(49,000)
Adjustments required by change in method of accounting as a result of adopting ASC 606	31,000
Return to provision		6,000
Impact of federal rate change		467,000
Increase (decrease) in valuation allowance	(217,000)	651,000
Total income tax provision (benefit)	$ 13,000	$ 681,000