Income Taxes - Summary of Principal Components of Company's Deferred Tax Assets (Details) - USD ($) $ in Thousands  | 
Dec. 31, 2020  | 
Dec. 31, 2019  | 
|---|---|---|
| Deferred tax assets: | ||
| Federal, state and local net operating loss carryforwards | $ 15,241 | $ 5,688 | 
| License fee deductions | 340 | 362 | 
| Research and development tax credits | 1,317 | 452 | 
| Stock-based compensation deductions | 1,243 | 264 | 
| Accrued expenses | 837 | 457 | 
| Gross deferred tax assets | 18,978 | 7,223 | 
| Less: valuation allowance | (18,978) | (7,223) | 
| Deferred tax liabilities: | ||
| Net deferred tax assets | $ 0 | $ 0 | 
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- Definition Deferred tax assets license fees deductions. 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, 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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- References No definition available. 
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local 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 research tax credit 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 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 accrued liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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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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