Stock-based Compensation - Exercised Options Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | |
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Dec. 31, 2018 |
Dec. 31, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Proceeds from exercise of stock options | $ 1 | $ 46 |
| Options to purchase common stock | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Proceeds from exercise of stock options | 1 | |
| Aggregate intrinsic value | $ 1 | $ 86 |
| Granted (in dollars per share) | $ 1.57 | $ 1.26 |
| Fair value of vested shares | $ 1,725 | $ 2,192 |
| Unrecognized compensation expense | $ 6,007 | |
| Period of unrecognized compensation expense | 2 years 10 months 24 days | |
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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 Unrecognized cost of unvested options awarded to employees as compensation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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