Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Schedule of fair value hierarchy for the Company’s financial assets and liabilities which require fair value measurement on a recurring basis

The following table represents the fair value hierarchy for the Company’s financial assets and liabilities which require fair value measurement on a recurring basis (in thousands):

	June 30, 2017
	Total		Level 1		Level 2		Level 3
Assets:
Money market	$	19,960	$	19,960			$	—
Corporate debt	43,120		—		43,120		—
U.S. Treasury notes	68,191		—		68,191		—
Total assets measured at fair value	$	131,271	$	19,960	$	111,311	$	—
Liabilities:
Embedded derivative liability	$	764	$	—	$	—	$	764
Total liabilities measured at fair value	$	764	$	—	$	—	$	764

	December 31, 2016
	Total		Level 1		Level 2		Level 3
Assets:
Money market	$	192	$	192	$	—	$	—
Corporate debt	51,233		—		51,233		—
U.S. Treasury notes	60,976		—		60,976		—
Total assets measured at fair value	$	112,401	$	192	$	112,209	$	—