Note 14 - Stock-based Compensation (Tables)

12 Months Ended

Mar. 29, 2015

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

Schedule of Share-based Compensation, Employee Stock Purchase Plan, Activity [Table Text Block]

	Shares of Common Stock		Weighted Average Price per Share
Authorized to issue:		4,500
Reserved for future issuance:
Fiscal year ending March 29, 2015		1,346
Fiscal year ending March 30, 2014		1,372
Fiscal year ending March 31, 2013		1,392
Issued:
Fiscal year ending March 29, 2015		26	$	10.01
Fiscal year ending March 30, 2014		20		11.38
Fiscal year ending March 31, 2013		26		8.38

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

				Options Outstanding						Options Exercisable
Range of				Number Outstanding As of March 29,		Weighted Average Remaining Contractual Terms		Weighted Average Exercise		Number Exercisable As of March 29,		Weighted Average Exercise
Exercise Prices				2015		(in years)		Price per Share		2015		Price per Share
	$1.57	-	$6.43		1,951,070		3.32	$	6.12		1,493,854	$	6.04
	6.60	-	8.51		1,693,928		4.29		7.85		909,929		7.79
	8.57	-	9.55		1,583,739		5.95		9.22		361,184		9.15
	9.57	-	11.64		1,594,345		5.86		10.55		358,156		10.73
	11.79	-	13.93		786,540		5.67		12.82		195,320		13.15
Total					7,609,622		4.86		8.77		3,318,443		7.78

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

	Outstanding Options / Quantity			Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)		In-the-money Options Vested and Exercisable (in thousands)
Balance at April 1, 2012		6,345,307		$	7.23		4.67	$	9,474		1,193
Granted		2,540,010			8.32
Exercised		(875,459	)		6.92
Cancelled		(903,781	)		9.67
Forfeited		(893,744	)		6.41
Balance at March 31, 2013		6,212,333		$	7.48		5.04	$	19,199		1,481
Granted		2,482,650			11.89
Exercised		(784,864	)		7.14
Cancelled		(10,834	)		10.92
Forfeited		(685,437	)		8.02
Balance at March 30, 2014		7,213,848		$	8.98		5.02	$	21,301		2,170
Granted		2,624,778			8.70
Exercised		(864,222	)		7.05
Cancelled		(291,769	)		12.36
Forfeited		(1,073,013	)		10.45
Balance at March 29, 2015		7,609,622		$	8.77		4.86	$	14,377		2,850
Vested and expected to vest, March 29, 2015		7,114,744		$	8.69		4.81	$	13,941
Vested and exercisable, March 29, 2015		3,318,443		$	7.78		3.96	$	9,100

Schedule of Cash Proceeds Received from Share-based Payment Awards [Table Text Block]

	March 29, 2015		March 30, 2014		March 31, 2013
Intrinsic value of options exercised	$	2,543	$	3,887	$	1,443
Cash received related to option exercises		6,095		9,493		6,059
Tax benefit recorded		1,655		6,669		1,927

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

	Shares			Weighted Average Grant-Date Fair Value		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Unvested at April 1, 2012		604,655		$	7.13		2.38	$	5,079
Granted		331,894			8.40
Issued and released		(125,095	)		7.10
Forfeited		(79,250	)		6.96
Unvested at March 31, 2013		732,204		$	7.73		1.72	$	7,688
Granted		828,995			13.06
Issued and released		(346,407	)		9.38
Forfeited		(37,666	)		9.52
Unvested at March 30, 2014		1,177,126		$	10.94		1.62	$	13,784
Granted		509,370			9.34
Issued and released		(414,242	)		10.28
Forfeited		(199,329	)		11.87
Unvested at March 29, 2015		1,072,925		$	10.26		1.50	$	11,051
Vested and expected to vest, March 29, 2015		829,673					1.42	$	8,546

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

	March 29, 2015			March 30, 2014			March 31, 2013
Expected term of options (years)		4.53 – 4.70			4.40 – 4.49			4.36
Risk-free interest rate		1.1 – 1.3	%		0.6 – 1.1	%		0.5 – 0.6	%
Expected volatility		32 - 33	%		32 - 35	%		37 - 42	%
Expected dividend yield		—			—			—
Weighted average grant date fair value	$	2.80		$	3.40		$	2.80

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	March 29, 2015		March 30, 2014		March 31, 2013
Cost of sales	$	1,105	$	714	$	469
Research and development		2,661		1,974		789
Selling, general and administrative		9,848		6,164		3,530
Total stock-based compensation expense	$	13,614	$	8,852	$	4,788

Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block]

	March 29, 2015				March 30, 2014				March 31, 2013
	Amount (in thousands)		Weighted Average Remaining Recognition Period (in years)		Amount (in thousands)		Weighted Average Remaining Recognition Period (in years)		Amount (in thousands)		Weighted Average Remaining Recognition Period (in years)
Options	$	8,579		2.3	$	9,958		2.7	$	6,269		2.8
Performance Options		380		1.9		242		2.2		502		2.6
RSUs		3,568		2.3		5,970		2.2		1,557		2.5
PRSUs		1,751		2.1		3,047		2.5		1,814		3.4
Total Stock-based compensation expense	$	14,278			$	19,217			$	10,142