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Fair Value (Tables)

12 Months Ended

Dec. 31, 2020

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

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		2020				2019
Beginning balance		$	6,929			$	916
Issuance of warrants			—				10,214
Exercises			—				(794	)
Change in fair value of warrants			(2,418	)			(3,407	)
Reclassification to equity			(4,504	)			—
Ending balance		$	7			$	6,929

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 fair value as of December 31, 2020 and 2019 was determined by using an option pricing model with the following assumptions. All outstanding Series T warrants expired unexercised in January 2021.

		As of December 31, 2020				As of December 31, 2019
Expected term		0.1 years				1.1 years
Common stock market price		$	2.02			$	2.40
Risk-free interest rate			0.08	%			1.59	%
Expected volatility			57	%			168	%
Resulting fair value (per warrant)		$	0.05			$	1.47

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 assumptions used in the Black Scholes option pricing model to determine the fair value of the Series U warrants were as follows:

		As of December 31, 2020				As of December 31, 2019
Expected term		3.75 years				4.75 years
Common stock market price		$	2.02			$	2.40
Risk-free interest rate			0.24	%			1.68	%
Expected volatility			149.0	%			134.5	%
Resulting fair value (per warrant)		$	1.56			$	1.94

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19279-110258

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