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Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2021

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		2021				2020
Beginning balance		$	7			$	6,929
Change in fair value of warrants			(6	)			(2,418	)
Reclassification to equity			—				(4,504	)
Ending balance		$	1			$	7

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, 2021				As of December 31, 2020
Expected term			2.75 years			3.75 years
Common stock market price		$	1.05			$	2.02
Risk-free interest rate			0.91	%			0.24	%
Expected volatility			143.2	%			149.0	%
Resulting fair value (per warrant)		$	0.58			$	1.56

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
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-Topic 820
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-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
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