Income Taxes (Details) - USD ($)	12 Months Ended
	Apr. 30, 2022	Apr. 30, 2021
Income Taxes (Details) [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 1,200,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	1,176	$ 0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	1,176	$ (119,000)
Research Tax Credit Carryforward [Member]
Income Taxes (Details) [Line Items]
Tax Credit Carryforward, Amount	1,000,000
Domestic Tax Authority [Member]
Income Taxes (Details) [Line Items]
Operating Loss Carryforwards	29,600,000
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	15,900,000
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration	13,700,000
Tax Credit Carryforward, Amount	9,900,000
Domestic Tax Authority [Member] | Annual Limitation [Member]
Income Taxes (Details) [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	$ 3,400,000