Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

Schedule of Fair Value of Financial Liabilities

The following table sets forth the fair value of the Company’s financial liabilities by level within the fair value hierarchy (in thousands):

	At March 31, 2018
	Level 1		Level 2		Level 3		Total
2017 Placement Warrants Liability	$	—	$	—	$	7,932	$	7,932
2016 Placement Warrants Liability		—		—		6,306		6,306
Total	$	—	$	—	$	14,238	$	14,238

	At December 31, 2017
	Level 1		Level 2		Level 3		Total
2017 Placement Warrants Liability	$	—	$	—	$	12,487	$	12,487
2016 Placement Warrants Liability		—		—		9,933		9,933
Total	$	—	$	—	$	22,420	$	22,420

Summary of Changes in Fair Value of Level 3 Financial Liabilities

The following table sets forth a summary of the changes in fair value of the Company’s Level 3 financial liabilities (in thousands):

	Three Months Ended March 31,
	2018			2017
Fair value, beginning of period	$	22,420		$	2,723
Issuance of 2017 Placement Warrants		—			3,373
Change in fair value of Level 3 financial liabilities		(8,182	)		15,231
Fair value, end of period	$	14,238		$	21,327