Income Taxes - Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands |
May 31, 2025 |
May 31, 2024 |
May 31, 2023 |
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| Components of Deferred Tax Assets and Liabilities [Abstract] | |||
| Net operating loss | $ 97,626 | $ 100,897 | |
| Credits | 2,063 | 2,063 | |
| ASC 718 expense on non-qualified stock options | 2,724 | 2,665 | |
| Accrued expenses | 272 | 411 | |
| Lease liability | 30 | 59 | |
| Inventory charges | 6,173 | 6,173 | |
| Inventory write-off | 1,953 | 1,953 | |
| Contingent liability | 9,150 | 9,202 | |
| Issued warrants | 2,901 | 3,000 | |
| Section 174 R&D costs | 3,179 | 2,056 | |
| Amortization | 155 | 207 | |
| Fixed assets | 4 | 5 | |
| Other | 0 | 0 | |
| Total gross deferred tax asset | 126,230 | 128,691 | |
| Less valuation allowance | (126,203) | (128,636) | $ (128,579) |
| Total deferred tax assets | 27 | 55 | |
| Right-of-use asset | (27) | (55) | |
| Total deferred tax liabilities | (27) | (55) | |
| Net deferred tax asset (liability) | $ 0 | $ 0 |
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- Definition Deferred Tax Assets, Amortization No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from contingent liability. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory write-off. No definition available.
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- Definition Amount of deferred tax assets attributable to taxable temporary differences from leasing arrangements. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from warrants issuance No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax liability attributable to deductible temporary differences from right of use asset. No definition available.
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- Definition Section 174 R&D costs for net deferred tax assets. No definition available.
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- References No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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