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Schedule of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Apr. 30, 2022	Apr. 30, 2021
Income Tax Disclosure [Abstract]
Computed expected tax benefit	(21.00%)	(21.00%)
State income taxes, net of federal benefit	5.20%	6.80%
Federal research and development tax credits	(0.60%)	(0.70%)
Foreign rate differential		(1.30%)
Other non-deductible expenses	(0.90%)	(0.60%)
Proceeds of sale of New Jersey tax benefits	(7.00%)
Other	1.30%	2.30%
Increase in valuation allowance	14.10%	14.50%
Income tax (benefit)	(8.90%)

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Effective income tax reconciliation proceeds of sale of new jersey tax benefits.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other nondeductible expenses.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit.

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