Income Taxes - Significant Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|---|---|---|---|
| Deferred tax assets: | |||
| Net operating loss carryforwards | $ 73,691 | $ 70,749 | $ 69,906 |
| Stock-based compensation | 1,075 | 1,180 | 1,904 |
| Reserves and allowances | 261 | 463 | 229 |
| U.S. tax credits and other credits | 12,692 | 12,550 | 12,270 |
| Capitalized research and development expenditures | 6,881 | 8,825 | 9,750 |
| Operating lease right-of-use assets | 0 | (1) | (32) |
| Operating lease liabilities | 0 | 2 | 33 |
| Other | 44 | 94 | 129 |
| Total deferred tax assets | 94,644 | 93,862 | 94,189 |
| Valuation allowance | (94,644) | (93,862) | (94,189) |
| Net deferred tax assets | $ 0 | $ 0 | $ 0 |
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- Definition Deferred tax assets operating lease liabilities. No definition available.
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- Definition Deferred tax assets operating lease right-of-use assets. No definition available.
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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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- References No definition available.
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from in-process research and development cost acquired in business combination or from joint venture formation or both. 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 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 share-based compensation. 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 reserves and accruals. 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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