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Fair Value - Schedule of Estimated Fair Value Determined Using Option Pricing Model Assumptions (Details) | Dec. 31, 2019 $ / shares | Sep. 25, 2019 $ / shares | Dec. 31, 2018 $ / shares
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Series U Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants expected term | 5 years |  |
Expected Term [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants expected term | 1 year 1 month 6 days |  | 2 years 1 month 6 days
Common Stock Market Price [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 2.40 |  | 14.50
Risk-free Interest Rate [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 0.0159 |  | 0.0248
Expected Volatility [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 1.68 |  | 1.25
Resulting Fair Value (Per Warrant) [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 1.47 |  | 6.50
Level 3 [Member] | Expected Term [Member] | Series T Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants expected term | 1 year 1 month 6 days |  | 2 years 1 month 6 days
Level 3 [Member] | Expected Term [Member] | Series U Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants expected term | 4 years 9 months | 5 years |
Level 3 [Member] | Common Stock Market Price [Member] | Series T Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 2.40 |  | 14.50
Level 3 [Member] | Common Stock Market Price [Member] | Series U Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 2.40 | 3.42 |
Level 3 [Member] | Risk-free Interest Rate [Member] | Series T Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 0.0159 |  | 0.0248
Level 3 [Member] | Risk-free Interest Rate [Member] | Series U Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 0.0168 | 0.0160 |
Level 3 [Member] | Expected Volatility [Member] | Series T Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 1.68 |  | 1.25
Level 3 [Member] | Expected Volatility [Member] | Series U Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 1.345 | 1.349 |
Level 3 [Member] | Resulting Fair Value (Per Warrant) [Member] | Series T Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 1.47 |  | 6.50
Level 3 [Member] | Resulting Fair Value (Per Warrant) [Member] | Series U Warrants [Member] |  |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |  |
Warrants measurement input | 1.94 | 2.90 |

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