Financial Instruments and Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2017

Investments, Debt and Equity Securities [Abstract]

Summary of Available-for-Sale Marketable Securities

The following table summarizes our investments by significant categories and fair value measurement on a recurring basis as of March 31, 2017 and December 31, 2016:

(in thousands)	Maturity  (in years)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
March 31, 2017
Level 1:
Investments:
U.S. treasuries	< 3	$	47,748	$	13	$	(93	)	$	47,668
Mutual funds	N/A	500		7		—			507
Total investments		$	48,248	$	20	$	(93	)	$	48,175
Level 2:
Certificates of deposit	< 1	$	2,320	$	—	$	—		2,320
Total									$	50,495
December 31, 2016
Level 1:
Investments
U.S. treasuries	< 3	$	51,376	$	25	$	(77	)	$	51,324
Mutual funds	N/A	500		5		—			505
Total investments		$	51,876	$	30	$	(77	)	$	51,829
Level 2:
Certificates of deposit	< 1	$	2,320	$	—	$	—		$	2,320
Total									$	54,149

Summary of Financial Assets Measured at Fair Value on Recurring Basis

The following table summarizes our investments by significant categories and fair value measurement on a recurring basis as of March 31, 2017 and December 31, 2016:

(in thousands)	Maturity  (in years)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
March 31, 2017
Level 1:
Investments:
U.S. treasuries	< 3	$	47,748	$	13	$	(93	)	$	47,668
Mutual funds	N/A	500		7		—			507
Total investments		$	48,248	$	20	$	(93	)	$	48,175
Level 2:
Certificates of deposit	< 1	$	2,320	$	—	$	—		2,320
Total									$	50,495
December 31, 2016
Level 1:
Investments
U.S. treasuries	< 3	$	51,376	$	25	$	(77	)	$	51,324
Mutual funds	N/A	500		5		—			505
Total investments		$	51,876	$	30	$	(77	)	$	51,829
Level 2:
Certificates of deposit	< 1	$	2,320	$	—	$	—		$	2,320
Total									$	54,149