Note 6 - Fair Value Measurements

3 Months Ended

Mar. 31, 2013

Fair Value Disclosures [Text Block]

Note 6 — Fair Value Measurements

The Company measures certain financial assets and liabilities at fair value on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. A three-tier fair value hierarchy is established in accounting standards which prioritizes the inputs used in measuring fair value as follows:

Level 1 - observable inputs such as quoted prices in active markets for identical assets or liabilities

Level 2 - inputs other than Level 1 inputs that are either directly or indirectly observable, such as quoted prices in active markets for similar assets or liabilities

Level 3 - unobservable inputs for which little or no market data exists, therefore requiring an entity to develop its own assumptions

The Company uses the market approach valuation technique to determine fair value for investment securities. The assets classified as Level 1 consist of money market funds for which original cost approximates fair value. The assets classified as Level 2 consist of certificates of deposit, commercial paper, municipal debt securities, government debt securities, and corporate debt securities, which are valued using quoted market prices or alternative pricing sources including transactions involving identical or comparable assets and models utilizing market observable inputs.

For those assets classified as Level 2 that are not in active markets, the Company obtained fair value from pricing sources using quoted market prices for identical or comparable instruments and based on pricing models which include all significant observable inputs, including maturity dates, issue dates, settlement date, benchmark yields, reported trades, broker-dealer quotes, issue spreads, benchmark securities, bids, offers and other market related data. These inputs are observable or can be derived from or corroborated by observable market data for substantially the full term of the asset.

Assets measured at fair value on a recurring basis at March 31, 2013 and December 31, 2012 were as follows:

			Fair Value Measurements at Reporting Date Using
Description	March 31, 2013		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents
Money market funds	$	51,210	$	51,210	$	-	$	-
Commercial paper		16,997		-		16,997		-
Municipal debt securities		25,113		-		25,113		-
Total cash equivalents		93,320		51,210		42,110		-
Short-term investments
Commercial paper		140,693		-		140,693		-
Municipal debt securities		118,460		-		118,460		-
Corporate debt securities		22,542		-		22,542		-
Government debt securities		3,002		-		3,002		-
Total short-term investments		284,697		-		284,697		-
Long-term investments
Municipal debt securities		10,476		-		10,476		-
Government debt securities		20,012		-		20,012		-
Total long-term investments		30,488		-		30,488		-
Total investment securities	$	408,505	$	51,210	$	357,295	$	-

			Fair Value Measurements at Reporting Date Using
Description	December 31, 2012		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents
Money market funds	$	3,689	$	3,689	$	-	$	-
Commercial paper		370		-		370		-
Municipal debt securities		70,245		-		70,245		-
Total cash equivalents		74,304		3,689		70,615		-
Short-term investments
Certificates of deposit		5,863		-		5,863		-
Commercial paper		81,767		-		81,767		-
Municipal debt securities		106,207		-		106,207		-
Corporate debt securities		33,297		-		33,297		-
Government debt securities		12,005		-		12,005		-
Total short-term investments		239,139		-		239,139		-
Long-term investments
Municipal debt securities		14,022		-		14,022		-
Government debt securities		10,008		-		10,008		-
Total long-term investments		24,030		-		24,030		-
Total investment securities	$	337,473	$	3,689	$	333,784	$	-

There were no significant transfers between Level 1 and Level 2 assets for the three months ended March 31, 2013 or during the year ended December 31, 2012.

The carrying value for all long-term debt, including current maturities, owed by the Company as of March 31, 2013 and December 31, 2012, approximates fair value. The Company has determined the estimated fair value of its debt to be Level 3 as certain inputs used are unobservable. The fair value of the Company's long-term debt was estimated using discounted cash flow assumptions based on the current rates available to the Company for debt of the same remaining maturities and consideration of default and credit risk.