Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Fair Value Hierarchy for Financial Assets Measured at Fair Value on Recurring Basis

The following table represents the fair value hierarchy for our financial assets (cash equivalents and marketable securities) measured at fair value on a recurring basis (in thousands):

	Level 1		Level 2		Level 3		Total
December 31, 2016
Money market funds	$	18,981	$	-	$	-	$	18,981
U.S. Treasuries		-		3,499		-		3,499
U.S. government agency securities		-		30,437		-		30,437
Corporate debt securities		-		24,941		-		24,941
Total	$	18,981	$	58,877	$	-	$	77,858
	Level 1		Level 2		Level 3		Total
December 31, 2015
Money market funds	$	21,193	$	-	$	-	$	21,193
U.S. government agency securities		-		17,622		-		17,622
Corporate debt securities		-		152,749		-		152,749
Total	$	21,193	$	170,371	$	-	$	191,564