Stock-based Compensation - Schedule of Recognized Stock-Based Compensation (Details) - USD ($) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
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| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Share-based compensation expense | $ 822,000 | $ 550,000 | $ 1,626,594 | $ 2,297,744 |
| Research and Development [Member] | ||||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Share-based compensation expense | 350,000 | 113,000 | 649,000 | 686,000 |
| General and Administrative [Member] | ||||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Share-based compensation expense | $ 472,000 | $ 437,000 | $ 977,000 | $ 1,612,000 |
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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 Amount of noncash expense for share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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