Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Fair Value Hierarchy for Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table presents our fair value hierarchy for assets and liabilities measured at fair value on a recurring basis as of December 31, 2016 and December 31, 2015 (in thousands):

	Fair value as of December 31, 2016
	Total		Level 1		Level 2		Level 3
Assets:
Cash equivalents	$	13,578	$	13,578	$	—	$	—
Corporate debt securities	49,120		—		49,120		—
Certificates of deposit	9,291		—		9,291		—
Commercial paper	1,247		—		1,247		—
U.S. treasury securities	1,000		—		1,000		—
Debt securities of U.S. government-sponsored agencies	512		—		512		—
	$	74,748	$	13,578	$	61,170	$	—

	Fair value as of December 31, 2015
	Total		Level 1		Level 2		Level 3
Assets:
Cash equivalents	$	15,152	$	15,152	$	—	$	—
Corporate debt securities	80,967		—		80,967		—
Certificates of deposit	13,640		—		13,640		—
Commercial paper	3,496		—		3,496		—
	$	113,255	$	15,152	$	98,103	$	—