Fair Value of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Summary of Financial Instruments Measured at Fair Value on Recurring Basis

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

	Fair Value Measurements at June 30, 2017
	Total		Level 1		Level 2		Level 3
Liabilities
Series A warrant liability	$	415	$	415	$	—	$	—
Series C warrant liability	24		—		—		24
Total liabilities	$	439	$	415	$	—	$	24
	Fair Value Measurements at December 31, 2016
	Total		Level 1		Level 2		Level 3
Liabilities
Series A warrant liability	$	194	$	194	$	—	$	—
Series C warrant liability	86		—		—		86
Total common stock warrant liability	$	280	$	194	$	—	$	86

Summary of Changes in Fair Value of Level1 and Level 3 Financial Instruments

The following table sets forth a summary of the changes in the fair value of the Company’s Level 1 and Level 3 warrants, which are treated as liabilities, as follows (dollars in thousands):

	Series A Warrant			Series C Warrant
	Number of Warrants	Liability		Number of Warrants	Liability
Balance at December 31, 2016	2,425,605	$	194	590,415	$	86
Change in value of Series A Warrants	—	221		—	—
Change in value of Series C Warrants	—	—		—	(62		)
Balance at June 30, 2017	2,425,605	$	415	590,415	$	24