Fair Value of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Fair Value Measurement

The following tables represent the financial instruments measured at fair value on a recurring basis on the financial statements of the Company and the valuation approach applied to each class of financial instruments at June 30, 2017, and December 31, 2016.

	June 30, 2017
	(in thousands)
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets:
Cash and cash equivalents
Money market funds	$	46,987	$	—	$	—	$	46,987
Commercial paper	—		5,386		—		5,386
Total cash and cash equivalents	46,987		5,386		—		52,373
Investments:
Certificates of deposit	—		12,410		—		12,410
US Treasury securities	7,025		—		—		7,025
US Agency securities	—		4,499		—		4,499
Commercial paper	—		5,141		—		5,141
Asset-backed securities	—		5,026		—		5,026
Corporate notes and bonds	—		38,508		—		38,508
Total investments	7,025		65,584		—		72,609
Total assets measured at fair value	$	54,012	$	70,970	$	—	$	124,982

	December 31, 2016
	(in thousands)
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets:
Cash and cash equivalents:
Money market funds	$	10,970	$	—	$	—	$	10,970
Investments:
Certificates of deposit	—		7,257		—		7,257
US Treasury securities	8,544		—		—		8,544
US Agency securities	—		4,501		—		4,501
Asset-backed securities	—		5,557		—		5,557
Corporate notes and bonds	—		32,660		—		32,660
Total investments	8,544		49,975		—		58,519
Total assets measured at fair value	$	19,514	$	49,975	$	—	$	69,489