Stock-based Compensation - Schedule of Recognized Stock-Based Compensation (Details) - USD ($) |
3 Months Ended | |
|---|---|---|
Mar. 31, 2019 |
Mar. 31, 2018 |
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| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Share-based compensation expense | $ 804,000 | $ 1,748,000 |
| Research and Development [Member] | ||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Share-based compensation expense | 299,000 | 573,000 |
| General and Administrative [Member] | ||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Share-based compensation expense | $ 505,000 | $ 1,175,000 |
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. 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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