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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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- Definition

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+ References

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- Definition

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- Definition

Amount, after accumulated amortization, of debt discount (premium).

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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.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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