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Income Taxes (Details Narrative) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Apr. 30, 2024 | Apr. 30, 2023
Operating Loss Carryforwards [Line Items] |  |
Income tax benefit | $ (1,254) | $ (278)
Deferred tax assets, valuation allowance | 60,322 | 54,644
Valuation allowance, deferred tax asset, increase (decrease), amount | 5,700 | 7,000
Net operating loss carry forwards | $ 231,400 |
Operating loss carryforwards, expiration description | begin to expire in fiscal 2024 |
Operating loss carryforwards subject to no expiration | $ 97,900 |
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. |
Maximum [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Income tax benefit, research and development expense | $ 20,000 |
State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Net operating loss carry forwards | $ 27,700 |
Operating loss carryforwards, expiration description | begin to expire in 2042, which also may be limited to utilization limitations. |
Foreign Tax Jurisdiction [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 | 4,300 |
New Jersey Division of Taxation [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Income tax benefit | $ 1,300 | $ 300

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