Fair Value (Tables)

6 Months Ended

Jun. 30, 2019

Fair Value Disclosures [Abstract]

Schedule of Fair Value Assumptions of Warrants and Embedded Conversion Feature

The fair value of the bifurcated embedded conversion feature was estimated to be approximately $7.2 million at March 5, 2018, as calculated using the Monte Carlo simulation with the following assumptions:

	Series F Conversion Feature
	March 5, 2018
Stock price	$	20.05
Exercise price	$	27.50
Risk-free rate		2.2	%
Volatility		88.2	%
Term		1.5

The fair value of the warrant liability was estimated to be approximately $2.5 million at March 5, 2018 as calculated using the Monte Carlo simulation with the following assumptions:

	Warrant Liability
	March 5, 2018
Stock price	$	20.05
Exercise price	$	30.00
Risk-free rate		2.2	%
Volatility		88.2	%
Term		1.5

Schedule of Changes in Estimated Fair Value for Level 3 Classified Derivative Warrant Liability

The following table sets forth the changes in the estimated fair value for our Level 3 classified derivative liabilities (in thousands):

	2017 Series F Preferred Stock – Warrant Liability			2017 Series F Preferred Stock – Embedded Derivative			Total Warrant and Derivative Liability
Fair value – December 31, 2017	$	3,388		$	8,150		$	11,538
Change in fair value		(863	)		(987	)		(1,850	)
Exchange / conversion to common shares		(2,525	)		(7,163	)		(9,688	)
Fair value – June 30, 2018	$	–		$	–		$	–

Schedule of Fair Value of Financial Instruments Measured on Recurring Basis

The following table sets forth the fair value of the Company’s financial assets and liabilities measured on a recurring basis by level within the fair value hierarchy as of June 30, 2019 and December 31, 2018 (in thousands):

	Fair Value Measurement as of June 30, 2019
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	37	$	–	$	–	$	37
Commercial paper		–		19,984		–		19,984
Corporate debt securities		–		12,342		–		12,342
U.S. government debt securities		–		8,105		–		8,105
Total	$	37	$	40,431	$	–	$	40,468
Liabilities:
Contingent consideration	$	–	$	–	$	135	$	135
Total	$	–	$	–	$	135	$	135

	Fair Value Measurement as of December 31, 2018
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	7	$	–	$	–	$	7
Commercial paper		–		21,392		–		21,392
Corporate debt securities		–		5,448		–		5,448
U.S. government debt securities		–		3,226		–		3,226
Total	$	7	$	30,066	$	–	$	30,073
Liabilities:
Contingent consideration	$	–	$	–	$	261	$	261
Total	$	–	$	–	$	261	$	261

Schedule of Changes in Estimated Fair Value for Level 3 Classified Contingent Consideration

The following table sets forth the changes in the estimated fair value of our contingent consideration liability (in thousands) which is included in other current liabilities:

	Contingent Consideration
Fair value – December 31, 2018	$	261
Change in fair value		(48	)
Earned and paid		(78	)
Fair value – June 30, 2019	$	135