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Fair Value (Tables)

6 Months Ended

Jun. 30, 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 Level 3 warrant liability value (in thousands):

	Three Months Ended							Six Months Ended
Warrant liability	June 30, 2020			June 30, 2019				June 30, 2020			June 30, 2019
Beginning balance	$	5,262		$	706			$	6,929		$	916
Change in fair value		(756	)		(282	)			(2,423	)		(492	)
Reclass to equity		(4,264	)		—				(4,264	)		—
Ending balance	$	242		$	424			$	242		$	424

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 estimated fair value of the Series T Warrants as of June 30, 2020 and December 31, 2019 was determined by using an option pricing model with the following assumptions. The Series T 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 and comprehensive loss.

		As of June 30, 2020				As of December 31, 2019
Expected term		0.8 years				1.1 years
Common stock market price		$	2.12			$	2.40
Risk-free interest rate			0.17	%			1.59	%
Expected volatility			119	%			168	%
Resulting fair value (per warrant)		$	0.82			$	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 Company estimated the fair value of the Series U Warrants with the Black Scholes model with the following assumptions. The Series U Warrants that have not been amended (Note 11) 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 and comprehensive loss.

		As of June 30, 2020				As of December 31, 2019
Expected term		4.2 years				4.75 years
Common stock market price		$	2.12			$	2.40
Risk-free interest rate			0.25	%			1.68	%
Expected volatility			142	%			135	%
Resulting fair value (per warrant)		$	1.64			$	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

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=117815213&loc=d3e19207-110258

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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=117815213&loc=d3e19207-110258

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-Publisher FASB
-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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