Provision for Income Taxes - Components of Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Components Of Deferred Tax Assets And Liabilities [Abstract] | |||
| Net operating losses | $ 30,112 | $ 13,844 | |
| Stock-based compensation | 7,141 | 3,416 | |
| Accrued expenses | 178 | 445 | |
| Research credits | 547 | 490 | |
| Other - fixed assets and intangibles | 13 | ||
| Other | 682 | 70 | |
| Gross deferred tax assets | 38,660 | 18,278 | |
| Less: valuation allowance | (35,233) | (18,278) | $ (9,852) |
| Total deferred tax assets | 3,427 | ||
| Other - fixed assets and intangibles | (3,427) | ||
| Total deferred tax liabilities | (3,427) | 0 | |
| Net deferred tax assets | $ 0 | $ 0 |
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://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 operating loss carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://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://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 reserves and accruals. 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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Deferred tax asset other - fixed assets and intangibles. No definition available.
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- Definition Deferred tax liabilities other - fixed assets and intangibles. No definition available.
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