Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2018

Fair Value Disclosures [Abstract]

Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring Basis

The following tables represent the Company’s financial assets and financial liabilities measured at fair value on a recurring basis categorized by the fair value hierarchy as of September 30, 2018 and December 31, 2017 (in thousands):

	As of September 30, 2018
	Level 1		Level 2		Level 3		Total
Financial asset— available-for-sales securities
Money market funds	$	4,911	$	—	$	—	$	4,911
Commercial Paper		—		9,875		—		9,875
Corporate bonds		—		49,130		—		49,130
U.S. government securities		—		1,500		—		1,500
Total financial asset—available-for-sales securities	$	4,911	$	60,505	$	—	$	65,416

	As of December 31, 2017
	Level 1		Level 2		Level 3		Total
Financial asset— available-for-sales securities
Money market funds	$	1,269	$	—	$	—	$	1,269
Commercial paper		—		13,916		—		13,916
Corporate bonds		—		36,453		—		36,453
U.S. government securities		—		2,485		—		2,485
Total financial asset—available-for-sales securities	$	1,269	$	52,854	$	—	$	54,123