(3) Cash, Cash Equivalents and Marketable Securities

A summary of cash, cash equivalents and available-for-sale marketable securities held by the Company as of September 30, 2013 and December 31, 2012 was as follows (see Note 2):

	September 30, 2013
	Cost		Unrealized gains		Unrealized losses		Fair value
	(in thousands)
Cash and cash equivalents:
Cash and money market funds (Level 1)	$	23,977	$	—	$	—	$	23,977
Corporate debt securities due within 3 months of date of purchase (Level 2)	1,500		—		—		1,500
Total cash and cash equivalents	$	25,477	$	—	$	—	$	25,477
Marketable securities (due within 1 year of date of purchase):
Corporate debt securities (Level 2)	27,901		6		—		27,907
Total marketable securities	27,901		6		—		27,907
Total cash, cash equivalents and marketable securities	$	53,378	$	6	$	—	$	53,384

	December 31, 2012
	Cost		Unrealized gains		Unrealized losses			Fair value
	(in thousands)
Cash and cash equivalents:
Cash and money market funds (Level 1)	$	81,512	$	—	$	—		$	81,512
Marketable securities:
Corporate debt securities due within 1 year of date of purchase (Level 2)	19,085		3		(1		)	19,087
Total cash, cash equivalents and marketable securities	$	100,597	$	3	$	(1	)	$	100,599