Fair Value Measurement (Tables)

9 Months Ended

Sep. 30, 2018

Fair Value Disclosures [Abstract]

Fair Value of Financial Assets and Liabilities

The following table sets forth the fair value of our financial assets and liabilities, allocated into Level 1, Level 2 and Level 3, that was measured on a recurring basis (in thousands):

	September 30, 2018
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	15,160	$	—	$	—	$	15,160
Corporate notes and commercial paper		—		78,241		—		78,241
U.S. treasury securities		—		13,936		—		13,936
U.S. government agency securities		—		33,301		—		33,301
Total financial assets	$	15,160	$	125,478	$	—	$	140,638
	December 31, 2017
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	12,430	$	—	$	—	$	12,430
Corporate notes and commercial paper		—		85,492		—		85,492
U.S. treasury securities		—		34,437		—		34,437
U.S. government agency securities		—		53,691		—		53,691
Total financial assets	$	12,430	$	173,620	$	—	$	186,050