Fair Value of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Assets measured at fair value on a recurring basis

The following table presents the financial instruments measured at fair value on a recurring basis and the valuation approach applied to each class of financial instruments as of June 30, 2017 and December 31, 2016 (in thousands):

	June 30, 2017
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Money market funds (cash equivalents)	$	75,191	$	—	$	—	$	75,191
Corporate notes and bonds	—		16,591		—		16,591
U.S. government and agency securities	—		1,500		—		1,500
Commercial paper	—		—		—		—
Total	$	75,191	$	18,091	$	—	$	93,282
	December 31, 2016
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Money market funds (cash equivalents)	$	556	$	—	$	—	$	556
Corporate notes and bonds	—		18,821		—		18,821
U.S. government and agency securities	—		3,503		—		3,503
Commercial paper	—		3,283		—		3,283
Total	$	556	$	25,607	$	—	$	26,163