Note 7 - Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

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

	Year Ended December 31,
	2014		2013		2012
Cost of revenue	$	903	$	631	$	510
Research and development		9,019		6,219		6,922
Selling, general and administrative		23,532		13,851		11,220
Tax benefit		-		-		(187	)
Total	$	33,454	$	20,701	$	18,465

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
	(in thousands)					(in thousands)					(in thousands)				(in thousands)
Outstanding at January 1, 2012		1,082		$	16.00		217		$	20.73		-	$	-		1,299		$	16.87
Modification (1)		(76	)	$	15.69		76		$	15.69		-	$	-		-		$	-
Granted (2)(3)		617		$	18.69		963		$	18.24		-	$	-		1,580		$	18.42
Performance adjustment (4)		-		$	-		(624	)	$	18.19		-	$	-		(624	)	$	18.19
Released		(447	)	$	17.30		(97	)	$	20.73		-	$	-		(544	)	$	17.91
Forfeited		(77	)	$	16.61		(4	)	$	19.07		-	$	-		(81	)	$	16.74
Outstanding at December 31, 2012		1,099		$	16.96		531		$	18.49		-	$	-		1,630		$	17.46
Granted (3)		299		$	24.25		875		$	24.43		1,800	$	23.57		2,974		$	23.89
Performance adjustment (4)		-		$	-		(124	)	$	21.98		-	$	-		(124	)	$	21.98
Released		(519	)	$	17.57		(206	)	$	18.90		-	$	-		(725	)	$	17.95
Forfeited		(125	)	$	17.06		(48	)	$	19.06		-	$	-		(173	)	$	17.61
Outstanding at December 31, 2013		754		$	19.41		1,028		$	23.02		1,800	$	23.57		3,582		$	22.53
Granted (3)(5)		335		$	36.71		1,091		$	34.23		-	$	-		1,426		$	34.82
Performance adjustment (4)		-		$	-		(139	)	$	31.40		-	$	-		(139	)	$	31.40
Released		(468	)	$	20.36		(304	)	$	18.12		-	$	-		(772	)	$	19.48
Forfeited		(32	)	$	19.75		(17	)	$	19.79		-	$	-		(49	)	$	19.77
Outstanding at December 31, 2014		589		$	28.48		1,659		$	28.11		1,800	$	23.57		4,048		$	26.14

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

	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic Value
	(in thousands)					(in years)		(in thousands)
Outstanding at January 1, 2012		4,863		$	15.31		3.4	$	8,817
Options granted (1)		178		$	15.63
Options exercised		(1,152	)	$	11.62
Options forfeited and expired		(76	)	$	20.90
Outstanding at December 31, 2012		3,813		$	15.62		2.6	$	25,380
Options exercised		(2,446	)	$	15.49
Options forfeited and expired		(11	)	$	15.27
Outstanding at December 31, 2013		1,356		$	15.86		1.9	$	25,506
Options exercised		(742	)	$	16.09
Options forfeited and expired		(24	)	$	10.07
Outstanding at December 31, 2014		590		$	15.80		1.2	$	20,039
Options exercisable at December 31, 2014 and expected to vest		590		$	15.80		1.2	$	20,026
Options exercisable at December 31, 2014		568		$	15.92		1.2	$	19,221

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

		Options Outstanding						Options Exercisable
Range of Exercises Prices		Shares		Weighted- Average Remaining Contractual Term		Weighted- Average Exercise Price		Shares		Weighted- Average Exercise Price
		(in thousands)		(in years)				(in thousands)
$	0.76 - $14.96		118		2.0	$	12.16		98	$	12.07
$	15.03 - $15.03		321		0.8	$	15.03		321	$	15.03
$	15.13 - $23.50		151		1.6	$	20.29		149	$	20.36
			590		1.2	$	15.80		568	$	15.92

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

	Year Ended
	December 31, 2012
Expected term (years)		4.1
Expected volatility		53.4	%
Risk-free interest rate		0.6	%
Dividend yield		-

	Year Ended December 31,
	2014			2013			2012
Expected term (years)		0.5			0.5			0.5
Expected volatility		29.4	%		28.0	%		45.8	%
Risk-free interest rate		0.1	%		0.1	%		0.1	%
Dividend yield		0.7	%		-			-