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Fair Value (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]

Schedule of Estimated Fair Value Determined Using Option Pricing Model Assumptions

		As of December 31, 2019				As of December 31, 2018
Expected term		1.1 years				2.1 years
Common stock market price		$	2.40			$	14.50
Risk-free interest rate			1.59	%			2.48	%
Expected volatility			168	%			125	%
Resulting fair value (per warrant)		$	1.47			$	6.50

Summary of Change in Level 3 Warrant Liability Value

The following table summarizes the change in our Level 3 warrant liability value (in thousands):

		Years ended December 31,
Warrant liability		2019				2018
Beginning balance		$	916			$	3,148
Issuance of warrants			10,214				—
Exercises			(794	)			—
Change in fair value			(3,407	)			(2,233	)
Ending balance		$	6,929			$	916

Fair Value and Carrying Value of Term Loan

At December 31, 2019 and 2018, the aggregate fair value and the carrying value of the Company’s term loan were as follows (in thousands):

		December 31, 2019								December 31, 2018
		Fair Value				Carrying Value				Fair Value				Carrying Value
Debt		$	10,761			$	11,060			$	14,043			$	14,202

Series T Warrants [Member]

Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]

Schedule of Estimated Fair Value Determined Using Option Pricing Model Assumptions

The Series T Warrants are not traded in an active securities market, and as such the estimated the fair value as of December 31, 2019 and 2018 was determined by using an option pricing model with the following assumptions:

		As of December 31, 2019				As of December 31, 2018
Expected term		1.1 years				2.1 years
Common stock market price		$	2.40			$	14.50
Risk-free interest rate			1.59	%			2.48	%
Expected volatility			168	%			125	%
Resulting fair value (per warrant)		$	1.47			$	6.50

Series U Warrants [Member]

Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]

Schedule of Estimated Fair Value Determined Using Option Pricing Model Assumptions

The Series U warrants will be marked to market as of each balance sheet date until they are exercised or upon expiration, with the changes in fair value recorded as non-operating income or loss in the statement of operations and comprehensive income (loss).

		As of December 31, 2019				As of September 25, 2019
Expected term		4.75 years				5 years
Common stock market price		$	2.40			$	3.42
Risk-free interest rate			1.68	%			1.60	%
Expected volatility			134.5	%			134.9	%
Resulting fair value (per warrant)		$	1.94			$	2.90

X

- Definition

Tabular disclosure of input and valuation technique used to measure fair value and change in valuation approach and technique used to measure similar asset in prior period by class of asset or liability on non-recurring basis.

+ References

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- Definition

Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.

+ References

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- Definition

Tabular disclosure of the fair value measurement of liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and gains or losses recognized in other comprehensive income (loss) and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs) by class of liability.

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