Note 5 — Marketable Securities

The Company invests in short-term and long-term agency, municipal, corporate, commercial paper and other debt securities. The securities are categorized as held-to-maturity and are recorded at amortized cost. Categorization as held-to-maturity is based on the Company’s ability and intent to hold these securities to maturity. Information regarding the Company’s short-term and long-term marketable securities as of March 31, 2013 and December 31, 2012 is as follows:


	March 31, 2013
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
U.S. government agency securities	$	23,714	$	8	$	(5	)	$	23,717
Corporate debt securities		23,767		29		(28	)		23,768
Commercial paper		5,493		—		(13	)		5,480
U.S. municipal securities		26,901		10		(14	)		26,897
Certificates of deposit/time deposits		4,697		8		(1	)		4,704

Total marketable securities	$	84,572	$	55	$	(61	)	$	84,566


	December 31, 2012
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
U.S. government agency securities	$	23,011	$	2	$	(4	)	$	23,009
Corporate debt securities		14,675		18		(14	)		14,679
Commercial paper		1,500		—		—			1,500
U.S. municipal securities		17,971		3		(12	)		17,962
Certificates of deposit/time deposits		4,945		3		(1	)		4,947

Total marketable securities	$	62,102	$	26	$	(31	)	$	62,097

Fair values for the U.S. government agency and corporate debt securities are primarily determined based on quoted market prices (Level 1). Fair values for the U.S. municipal securities, certificates of deposit and commercial paper are primarily determined using dealer quotes or quoted market prices for similar securities (Level 2).

The Company tests for other than temporary losses on a quarterly basis and has considered the unrealized losses indicated above to be temporary in nature. The Company intends to hold the investments to maturity and recover the full principal.

Classification of marketable securities as current or non-current is based upon the security’s maturity date as of the date of these financial statements.

The March 31, 2013 balance of held-to-maturity debt securities by contractual maturity is shown in the following table at amortized cost. Actual maturities may differ from contractual maturities because the issuers of the securities may have the right to prepay obligations without prepayment penalties.


	March 31,
(in thousands)	2013
Due in one year or less	$	35,695
Due after one year through five years		48,877

Total marketable securities	$	84,572