MARKETABLE SECURITIES

Marketable securities classified as available-for-sale consisted of the following (in thousands):



	September 30, 2014
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Fair Value
Corporate bonds	$	69,856	$	33	$	(90	)	$	69,799
Asset-backed securities	56,285		13		(36		)	56,262
Commercial paper	30,596		2		—			30,598
Mortgage-backed securities	21,348		31		(81		)	21,298
Government and agency securities	9,208		7		(5		)	9,210
Municipal bonds	2,704		5		—			2,709
Total	$	189,997	$	91	$	(212	)	$	189,876



	December 31, 2013
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Fair Value
Corporate bonds	$	45,414	$	75	$	(7	)	$	45,482
Asset-backed securities	21,222		12		(8		)	21,226
Mortgage-backed securities	15,110		33		(26		)	15,117
Commercial paper	13,890		2		—			13,892
Government and agency securities	12,255		9		—			12,264
Municipal bonds	3,817		—		(4		)	3,813
Certificates of deposit	750		—		—			750
Total	$	112,458	$	131	$	(45	)	$	112,544

The following table summarizes the amortized cost and fair value of the Company’s marketable securities, classified by stated maturity as of September 30, 2014 and December 31, 2013 (in thousands):



	September 30, 2014				December 31, 2013
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Marketable securities
Due in 1 year or less	$	62,295	$	62,305	$	59,384	$	59,448
Due in 1-2 years	53,133		53,116		21,628		21,641
Due in 2-3 years	36,349		36,300		10,063		10,060
Due in 3-4 years	10,958		10,961		—		—
Due in 4-9 years	10,404		10,402		7,587		7,610
Due in 9-20 years	1,350		1,361		1,629		1,639
Due in 20-33 years	15,508		15,431		12,167		12,146
	$	189,997	$	189,876	$	112,458	$	112,544

Marketable securities classified as available-for-sale are carried at fair value as of September 30, 2014 and December 31, 2013. Realized gains and losses from sales and maturities of marketable securities were not significant in the periods presented.

The aggregate fair value of available-for-sale securities with unrealized losses was $95.3 million as of September 30, 2014. Gross unrealized losses on available-for-sale securities were $0.2 million as of September 30, 2014, and the Company believes the gross unrealized losses are temporary. In determining that the decline in fair value of these securities was temporary, the Company considered the length of time each security was in an unrealized loss position and the extent to which the fair value was less than cost. The aggregate fair value and unrealized loss of available-for-sale securities which had been in a continuous loss position for more than 12 months was $2.7 million and $27,000 as of September 30, 2014, respectively. In addition, the Company does not intend to sell these securities and it is more likely than not that the Company will not be required to sell these securities before the recovery of their amortized cost basis.