Income taxes - Deferred (Details) - USD ($) $ in Thousands |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Deferred tax assets: | ||
| Net operating loss carryforwards | $ 46,665 | $ 35,045 |
| Capitalized start-up costs and research expenses | 18,169 | 20,137 |
| Research and development credits | 8,824 | 8,265 |
| Accruals, reserves and other | 313 | 270 |
| Stock compensation | 3,439 | 2,674 |
| Lease liabilities | 16 | 16 |
| Total gross deferred assets | 77,426 | 66,407 |
| Valuation allowance | (77,410) | (66,391) |
| Total deferred tax assets | 16 | 16 |
| Deferred tax liabilities: | ||
| Right-of-use assets | (16) | (16) |
| Total deferred liabilities | (16) | (16) |
| Net deferred tax assets | $ 0 | $ 0 |
| X | ||||||||||
- Definition Amount of deferred tax asset attributable to taxable temporary differences from Capitalized start-up costs and research expenses. No definition available.
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- Definition Amount of deferred tax asset 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 and carryforwards. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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 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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- References No definition available.
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| X | ||||||||||
- 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 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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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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