Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Schedule of fair value of financial instruments

The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands): 

	December 31, 2018
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	—	$	—	$	—	$	3
Corporate fixed income debt securities		—		—		—		—
Total	$	—	$	—	$	—	$	—
Financial Liabilities:
Common stock warrant liability (1)	$	—	$	—	$	—	$	—
Total	$	—	$	—	$	—	$	—

	December 31, 2017
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	3	$	—	$	—	$	3
Corporate fixed income debt securities		—		5,023		—		5,023
Total	$	3	$	5,023	$	—	$	5,026
Financial Liabilities:
Common stock warrant liability (1)	$	—	$	—	$	—	$	—
Total	$	—	$	—	$	—	$	—

(1) The change in the fair value of the common stock warrant and convertible notes payable for the twelve months ended December 31, 2018 and 2017 was recorded as a decrease to other income (expense) and interest expense of $1 and $1, respectively, in the statements of operations and comprehensive loss.