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Income Taxes (Details Narrative) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Apr. 30, 2025 | Apr. 30, 2024
Operating Loss Carryforwards [Line Items] |  |
Income tax benefit | $ (1,034) | $ (1,254)
Deferred tax assets, valuation allowance | 62,192 | 60,322
Valuation allowance, deferred tax asset, increase (decrease), amount | 1,900 | 5,700
Net operating loss carry forwards | $ 250,000 |
Operating loss carryforwards, expiration description | begin to expire in fiscal 2026 |
Operating loss carryforwards subject to no expiration | $ 116,200 |
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 | $ 28,300 |
Operating loss carryforwards, expiration description | begin to expire in 2042 |
Research and Development Expense [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax credit carryforward, amount | $ 5,200 |
New Jersey Division of Taxation [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Income tax benefit | $ 1,000 | $ 1,300

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