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Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 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 Level 3 warrant liability value for the three and nine months ended September 30, 2021 and 2020 (in thousands):

	Three Months Ended							Nine Months Ended
Warrant liability	September 30, 2021			September 30, 2020				September 30, 2021			September 30, 2020
Beginning balance	$	5		$	242			$	7		$	6,929
Change in fair value		(2	)		81				(4	)		(2,342	)
Reclassification to equity		—			(240	)			—			(4,504	)
Ending balance	$	3		$	83			$	3		$	83

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 Company estimated the fair value of the Series U Warrants with the Black Scholes model. 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 statements of operations.

		September 30, 2021				December 31, 2020
Expected term		3 years				3.75 years
Common stock market price		$	1.91			$	2.02
Risk-free interest rate			0.53	%			0.24	%
Expected volatility			139	%			149	%
Resulting fair value (per warrant)		$	1.25			$	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

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 (bbb)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

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+ 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.

+ 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)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19279-110258

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