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v3.23.2

Income Taxes (Details Narrative) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Apr. 30, 2023 | Apr. 30, 2022
Operating Loss Carryforwards [Line Items] |  |
Deferred Tax Assets, Valuation Allowance | $ 54,644 | $ 47,597
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | 7,000 | 2,500
Net operating loss carry forwards | $ 207,800 |
Operating loss carryforwards, expiration description | begin to expire in fiscal 2023 |
Operating loss carryforwards subject to no expiration | $ 72,800 |
Operating loss carryforwards, expiration description | the deductibility of such federal net operating losses may be limited to 80% of our taxable income in future years. |
Income tax benefit | $ (278) | (1,823)
Description of tax credit carryforward, limitations on use | Expenses incurred in connection with R&E activities in the US must be amortized over a 5-year period if incurred, and R&E expenses incurred outside the US must be amortized over a 15-year period. |
Maximum [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Income tax benefit, net operating losses | $ 20,000 |
Income tax benefit, research and development expense | 20,000 |
New Jersey Division of Taxation [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Income tax benefit | 300 | $ 1,400
State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Net operating loss carry forwards | $ 22,500 |
Operating loss carryforwards, expiration description | begin to expire in 2042, which also may be limited to utilization limitations. |
Foreign Tax Authority [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Net operating loss carry forwards | $ 10,800 |
Research and Development Expense [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | $ 4,000 |

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