Note 2 - Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2014

Note 2 - Stock-Based Compensation (Tables) [Line Items]

Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]

	Three Months Ended September 30,					Nine Months Ended September 30,
	2014		2013			2014		2013
Cost of revenue	$	246	$	163		$	669	$	465
Research and development		2,388		1,491			6,638		4,557
Selling, general and administrative		6,225		3,577			17,565		10,059
Tax benefit		-		(80	)		-		(175	)
Total stock-based compensation expense	$	8,859	$	5,151		$	24,872	$	14,906

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]

	Time-Based RSUs			Weighted- Average Grant Date Fair Value Per Share		PSUs					Weighted- Average Grant Date Fair Value Per Share	MSUs		Weighted- Average Grant Date Fair Value Per Share		Total			Weighted- Average Grant Date Fair Value Per Share
Outstanding at January 1, 2014		754,306		$	19.41		1,027,782			$	23.02		1,800,000	$	23.57		3,582,088		$	22.53
Awards granted		312,697			36.52		1,091,001		(1)		34.23		-		-		1,403,698			34.74
Performance adjustment		-			-		(141,626	)	(2)		31.54		-		-		(141,626	)		31.54
Awards released		(378,142	)		19.76		(276,512	)			18.12		-		-		(654,654	)		19.07
Awards forfeited		(24,039	)		19.81		(17,097	)			19.79		-		-		(41,136	)		19.80
Outstanding at September 30, 2014		664,822			27.25		1,683,548				27.87		1,800,000		23.57		4,148,370			25.90

Employee Stock Purchase Program [Member]

Note 2 - Stock-Based Compensation (Tables) [Line Items]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Three Months Ended September 30,						Nine Months Ended September 30,
	2014			2013			2014			2013
Expected term (years)		0.5			0.5			0.5			0.5
Expected volatility		25.1	%		27.5	%		29.5	%		28.0	%
Risk-free interest rate		0.1	%		0.1	%		0.1	%		0.1	%
Dividend yield		1.4	%		-			0.7	%		-

Plan Status [Member]

Note 2 - Stock-Based Compensation (Tables) [Line Items]

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Stock Options			Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding at January 1, 2014		1,356,446		$	15.86		1.9	$	25,505,753
Options exercised		(638,018	)		16.30
Options forfeited and expired		(8,397	)		11.22
Outstanding at September 30, 2014		710,031			15.51		1.3		20,265,815
Options exercisable at September 30, 2014 and expected to vest		709,524			15.52		1.3		20,245,815
Options exercisable at September 30, 2014		677,985			15.63		1.2		19,268,944