Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2019

Investments, Debt and Equity Securities [Abstract]

Summary of marketable securities

The following is a summary of our marketable securities as of September 30, 2019 and December 31, 2018 (in thousands):

	September 30, 2019
			Gross		Gross			Estimated
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
Short-term marketable securities:*
Corporate debt securities	$	41,596	$	130	$	(9	)	$	41,717
Certificates of deposit	3,500		—		—			3,500
U.S. treasury and government agency securities	6,247		—		(3		)	6,244
Commercial paper	—		—		—			—
Total short-term marketable securities	$	51,343	$	130	$	(12	)	$	51,461
Long-term marketable securities:**
Corporate debt securities	$	20,076	$	207	$	—		$	20,283
Total long-term marketable securities	20,076		207		—			20,283
Total marketable securities	$	71,419	$	337	$	(12	)	$	71,744

* Represents marketable securities with a remaining maturity of less than one year.

** Represents marketable securities with a remaining maturity of one to three years classified as short-term on our condensed consolidated balance sheets.

	December 31, 2018
			Gross		Gross			Estimated
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
Short-term marketable securities:*
Corporate debt securities	$	51,184	$	—	$	(236	)	$	50,948
U.S. treasury and government agency securities	7,647		—		(34		)	7,613
Commercial paper	3,995		—		—			3,995
Certificates of deposit	12,000		—		—			12,000
Total short-term marketable securities	$	74,826	$	—	$	(270	)	$	74,556
Long-term marketable securities:**
Corporate debt securities	$	62,530	$	52	$	(433	)	$	62,149
U.S. treasury and government agency securities	2,742		—		(32		)	2,710
Certificates of deposit	1,500		—		—			1,500
Total long-term marketable securities	66,772		52		(465		)	66,359
Total marketable securities	$	141,598	$	52	$	(735	)	$	140,915

* Represents marketable securities with a remaining maturity of less than one year.

** Represents marketable securities with a remaining maturity of one to three years classified as short-term on our condensed consolidated balance sheets.