Income Taxes - Additional Information (Detail) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Income Taxes Disclosure [Line Items] | |||
| Income tax (benefit) provision | $ 0 | $ 0 | $ (202,000) |
| NOL DTA related to excess benefits from stock option exercises | 500,000 | ||
| Increase (decrease) in valuation allowance | 9,000,000 | (6,200,000) | $ 7,800,000 |
| Accrued interest or penalties | 0 | $ 0 | |
| Federal | |||
| Income Taxes Disclosure [Line Items] | |||
| Net operating loss carryforwards | $ 143,000,000 | ||
| Year net operating loss carryforwards begin to expire | 2021 | ||
| Research and development credits | $ 10,500,000 | ||
| Year research and development credits begin to expire | 2022 | ||
| State | |||
| Income Taxes Disclosure [Line Items] | |||
| Net operating loss carryforwards | $ 94,000,000 | ||
| Year net operating loss carryforwards begin to expire | 2017 | ||
| Research and development credits | $ 5,900,000 | ||
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- Definition Income taxes disclosure. No definition available.
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- Definition Amount of net operating loss deferred tax assets related to excess benefits from stock option exercises. No definition available.
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- Definition Operating loss carryforward expiration start year. No definition available.
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- Definition Research and development tax credits expiration start year. No definition available.
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- Definition The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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