Income Taxes - Schedule of Significant Components of Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Income Tax Disclosure [Abstract] | ||
| Capitalized start-up costs | $ 78 | $ 103 |
| Net operating loss carryforwards | 54,250 | 47,725 |
| Research and development credits | 13,761 | 11,354 |
| Deferred stock compensation | 5,191 | 5,130 |
| Other (accruals, reserves, depreciation) | 362 | 359 |
| Total deferred tax assets | 73,642 | 64,671 |
| Less: Valuation allowance | (73,642) | (64,671) |
| Net deferred tax assets | $ 0 | $ 0 |
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- Definition Deferred tax assets capitalized start up costs. 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/presentationRef
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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/2003/role/presentationRef
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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/2003/role/presentationRef
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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/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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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/2003/role/presentationRef
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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/presentationRef
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- References No definition available.
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