Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2017

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 September 30, 2017	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market fund	$	24,111	$	—	$	—	$	24,111
Short-term investments:
Corporate debt securities	—		48,070		—		48,070
U.S. government-related debt securities	—		12,981		—		12,981
Total	$	24,111	$	61,051	$	—	$	85,162
As of December 31, 2016	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market fund	$	16,715	$	—	$	—	$	16,715
Short-term investments:
Corporate debt securities	—		36,160		—		36,160
U.S. government-related debt securities	—		17,293		—		17,293
Total	$	16,715	$	53,453	$	—	$	70,168