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Stockholders' Equity - Schedule of Estimated Fair Value Determined Using Option Pricing Model Assumptions (Details) | Sep. 30, 2019 $ / shares | Sep. 25, 2019 $ / shares | Dec. 31, 2018 $ / shares
--- | --- | --- | ---
Series U Warrants [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants expected term | 5 years |  |
Expected Term [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants expected term | 1 year 7 months 6 days |  | 2 years 1 month 6 days
Expected Term [Member] | Series U Warrants [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants expected term | 5 years | 5 years |
Common Stock Market Price [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants measurement input | 3.42 |  | 14.50
Common Stock Market Price [Member] | Series U Warrants [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants measurement input | 3.42 | 3.42 |
Risk-free Interest Rate [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants measurement input | 0.0170 |  | 0.0248
Risk-free Interest Rate [Member] | Series U Warrants [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants measurement input | 0.0155 | 0.0160 |
Expected Volatility [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants measurement input | 1.76 |  | 1.25
Expected Volatility [Member] | Series U Warrants [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants measurement input | 1.349 | 1.349 |
Resulting Fair Value (Per Warrant) [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants measurement input | 2.53 |  | 0.13
Resulting Fair Value (Per Warrant) [Member] | Series U Warrants [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Warrants measurement input | 2.90 | 2.90 |

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