Equity Inventive Plans, Employee Stock Purchase Plan and Stock-Based Compensation - Summary of Option Activity (Details) - 2004 and 2018 Equity Incentive Plan - USD ($) $ / shares in Units, $ in Thousands |
6 Months Ended | 12 Months Ended |
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Jun. 30, 2019 |
Dec. 31, 2018 |
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| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
| Outstanding Options, Beginning Balance | 3,111,718 | |
| Outstanding Options Granted | 885,260 | |
| Outstanding Options Exercised | (10,109) | |
| Outstanding Options Canceled | (83,216) | |
| Outstanding Options, Ending Balance | 3,903,653 | 3,111,718 |
| Weighted - Average Exercise Price, Beginning Balance | $ 13.74 | |
| Weighted - Average Exercise Price, Granted | 10.57 | |
| Weighted - Average Exercise Price, Exercised | 5.21 | |
| Weighted - Average Exercise Price, Canceled | 14.80 | |
| Weighted - Average Exercise Price, Ending Balance | $ 13.02 | $ 13.74 |
| Weighted - Average Remaining Contract Term | 8 years 6 months | 8 years 9 months 3 days |
| Aggregate Intrinsic Value, Balance | $ 2,462 | $ 1,088 |
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- Definition Share based compensation arrangement by share based payment award options canceled in period. No definition available.
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- Definition Share based compensation arrangements by share based payment award options canceled in period weighted average exercise price. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
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- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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