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Fair Value - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Carrying Value [Member] |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |
Debt discount | $ 0.4 | $ 0.6
2018 Rights Offering [Member] |  |
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] |  |
Redemption price of warrant prior to expiration | $ 0.01 |
Common stock price per share for warrant redemption | $ 3.63 |
Number of consecutive trading days for warrant redemption | 20 years |
Warrants liability fair value | $ 0.1 | $ 3.1

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