Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2016

Assets Measured at Fair Value on Recurring Basis

The Company held certain assets that are required to be measured at fair value on a recurring basis as of December 31, 2016, as follows:

			Fair Value Measurement as of December 31, 2016 Using
(in thousands)	December 31, 2016		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Available-for-sale securities:
U.S. Treasury and government agencies	$	50,647	$	50,647	$	—	$	—
Corporate debt		50,267		—		50,267
	$	100,914	$	50,647	$	50,267	$	—

The Company held certain assets that are required to be measured at fair value on a recurring basis as of December 31, 2015, as follows:

			Fair Value Measurement as of December 31, 2015 Using
(in thousands)	December 31, 2015		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Available-for-sale securities:
U.S. Treasury and government agencies	$	44,057	$	44,057	$	—	$	—
Corporate debt		48,280		—		48,280
	$	92,337	$	44,057	$	48,280	$	—