Note 4 - Marketable Securities

3 Months Ended

Mar. 31, 2014

Investments Schedule [Abstract]

Investment [Text Block]

Note 4 – 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, 2014 and December 31, 2013 is as follows:

	March 31, 2014
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
U.S. government agency securities	$	24,476	$	1	$	(63	)	$	24,414
Corporate debt securities		37,314		30		(76	)		37,268
Commercial paper		1,996		-		(15	)		1,981
U.S. municipal securities		36,949		60		(10	)		36,999
Certificates of deposit/time deposits		4,940		8		(2	)		4,946
Total marketable securities	$	105,675	$	99	$	(166	)	$	105,608

	December 31, 2013
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
U.S. government agency securities	$	21,713	$	2	$	(22	)	$	21,693
Corporate debt securities		29,480		30		(20	)		29,490
U.S. municipal securities		44,474		49		(22	)		44,501
Certificates of deposit/time deposits		4,695		5		(8	)		4,692
Total marketable securities	$	100,362	$	86	$	(72	)	$	100,376

Fair values for the corporate debt securities are primarily determined based on quoted market prices (Level 1).  Fair values for the U.S. municipal securities, U.S. government agency 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, 2014 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.

(in thousands)	March 31, 2014
Due in one year or less	$	34,360
Due after one year through five years		71,315
Total marketable securities	$	105,675