Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2016

Fair Value Disclosures [Abstract]

Fair Value of Financial Assets Measured on Recurring Basis

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

	June 30, 2016
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	32,579	$	—	$	—	$	32,579
Corporate notes and commercial paper	—			194,158		—		194,158
U.S. government agency securities		—		110,646		—		110,646
Total financial assets	$	32,579	$	304,804	$	—	$	337,383
	December 31, 2015
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	22,074	$	—	$	—	$	22,074
Corporate notes and commercial paper		—		242,033		—		242,033
U.S. government agency securities		—		180,876		—		180,876
Total financial assets	$	22,074	$	422,909	$	—	$	444,983