Income taxes - Deferred taxes (Details) - USD ($) $ in Thousands |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Deferred tax assets: | ||
| Net operating loss carryforwards | $ 13,693 | $ 10,202 |
| Research and development credits | 1,560 | 1,355 |
| Share-based compensation | 82 | 194 |
| Accrued bonus | 201 | 120 |
| Amortization | 2 | 3 |
| Gross deferred tax assets | 15,538 | 11,874 |
| Less: valuation allowance | (15,435) | (11,711) |
| Net deferred tax asset | 103 | 163 |
| Deferred tax liability | ||
| Depreciation | (103) | (163) |
| Total deferred tax liabilities |
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from 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 depreciation. 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 allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination. 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://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 from employee bonuses. 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 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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- References No definition available.
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