Note 8 - Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2012

Fair Value, by Balance Sheet Grouping [Table Text Block]

	Estimated Fair Market Value as of
	June 30, 2012		December 31, 2011
	(In thousands)
Cash, Cash Equivalents and Investments
Cash in Banks		51,530		43,305
Money Market Funds		30,114		51,066
Government Agencies/ Treasuries		103,013		79,827
Auction-Rate Securities backed by Student-Loan Notes		11,714		13,675
Total Cash, Cash Equivalents and Investments		196,371		187,873

Schedule of Other Current Assets [Table Text Block]

Reported as:
Cash and Cash Equivalents	81,644	96,371
Short-term Investments	103,013	77,827
Long-term Investments	11,714	13,675
Total Cash, Cash Equivalents and Investments	196,371	187,873

Investments Classified by Contractual Maturity Date [Table Text Block]

	June 30, 2012		December 31, 2011
Less than 1 year		25,992		45,133
1 - 5 years		77,021		32,694
Greater than 5 years		11,714		13,675
		114,727		91,502

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

	Fair Value Measurements at June 30, 2012 Using
			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total		Level 1		Level 2		Level 3
Money Market Funds	$	30,114	$	30,114	$	-	$	-
US Treasuries and US Government Agency Bonds		103,013		-		103,013		-
Long-term available-for-sale auction-rate securities		11,714		-		-		11,714
	$	144,841	$	30,114	$	103,013	$	11,714

	Fair Value Measurements at December 31, 2011 Using
			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total		Level 1		Level 2		Level 3
Money Market Funds	$	51,066	$	51,066	$	-	$	-
US Treasuries and US Government Agency Bonds		79,827		-		79,827		-
Long-term available-for-sale auction-rate securities		13,675		-		-		13,675
	$	144,568	$	51,066	$	79,827	$	13,675

Unrealized Gain (Loss) on Investments [Table Text Block]

	As of June 30, 2012
	Adjusted Cost		Unrealized Gains or Losses			Total Fair Value		Fair Value of Investments in Unrealized Loss Position
Money Market Funds	$	30,114		-		$	30,114		-
US Treasuries and US Government Agency Bonds		103,017		(4	)		103,013		51,858
Auction-rate securities backed by Student-Loan Notes		12,245		(531	)		11,714		11,714
		145,376		(535	)		144,841		63,572

	As of December 31, 2011
	Adjusted Cost		Unrealized Gains or Losses			Total Fair Value		Fair Value of Investments in Unrealized Loss Position
Money Market Funds	$	51,066	$	-		$	51,066	$	-
US Treasuries and US Government Agency Bonds		79,830		(3	)		79,827		25,281
Auction-rate securities backed by Student-Loan Notes		14,305		(630	)		13,675		13,675
	$	145,201	$	(633	)	$	144,568	$	38,956

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

	Auction-Rate Securities
Ending balances at December 31, 2011	$	13,675
Sales and Settlement at Par		(100	)
Total realized and unrealized gains (losses):
Included in other income (expense)		-
Included in other comprehensive income		90
Ending balances at March 31, 2012	$	13,665
Sales and Settlement at Par		(2,000	)
Total realized and unrealized gains (losses):
Included in other income (expense)		40
Included in other comprehensive income		9
Ending balances at June 30, 2012	$	11,714