Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2015

Fair Value Disclosures [Abstract]

Company's Available-for-Sale Securities by Level within Fair Value Hierarchy

The Company’s available-for-sale securities by level within the fair value hierarchy were as follows (in thousands):

As of March 31, 2015	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market fund	$	12,722	$	—	$	—	$	12,722
Short-term investments:
Corporate debt securities		—		38,742		—		38,742
Asset-backed securities		—		2,418		—		2,418
Total	$	12,722	$	41,160	$	—	$	53,882

As of December 31, 2014	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market fund	$	13,426	$	—	$	—	$	13,426
Short-term investments:
U.S. government-related debt securities		—		4,498		—		4,498
Corporate debt securities		—		47,307		—		47,307
Asset-backed securities		—		3,197		—		3,197
Total	$	13,426	$	55,002	$	—	$	68,428