Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2016

Fair Value Measurements

Schedule of financial assets and liabilities at fair value

	Level 1		Level 2		Level 3		Total
	(in thousands)
At September 30, 2016
Assets:
Cash and cash equivalents	$	3,415	$	—	$	—	$	3,415
Trade accounts receivable		506		—		—		506
Short-term investments		456		—		—		456
	$	4,377	$	—	$	—	$	4,377
Liabilities:
Warrant liability	$	—	$	—	$	3,031	$	3,031
	$	—	$	—	$	3,031	$	3,031
At December 31, 2015
Assets:
Cash and cash equivalents	$	4,077	$	—	$	—	$	4,077
Trade accounts receivable		546		—		—		546
Short-term investments		72		—		—		72
	$	4,695	$	—	$	—	$	4,695
Liabilities:
Warrant liability	$	—	$	—	$	210	$	210
Derivative liability		—		—		488		488
	$	—	$	—	$	698	$	698

Schedule of significant inputs to the valuation model

	September 30,		December 31,
	2016		2015
Company's ending stock price	$	0.76	$	0.20
Company's stock volatility		110%		85%
Applicable risk free interest rate		0.87%		1.48%

Summary of change in fair value of the warrant liability

	Fair Value Measurements
	Using Significant Unobservable
	Inputs (Level 3)
	Warrant Liabilities		Derivative  Liability
	(in thousands)
Ending balance at December 31, 2015	$	210	$	488
Conversion of Sentient Loan (see Note 11)		—		(488)
Change in estimated fair value		2,821		—
Ending balance at September 30, 2016	$	3,031	$	—