Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 28, 2015	Mar. 28, 2015	Mar. 29, 2014	Mar. 30, 2013
ReconciliationOfProvisionOfIncomeTaxes [Line Items]
Income tax expense at statutory federal rate		$ (42,434)	$ (8,355)	$ 9,065
Income tax expense at statutory federal rate, Percentage		35.00%	35.00%	35.00%
Decrease (increase) resulting from:
State benefit (provision), net of federal (provision) benefit		(6,710)	75	(827)
State benefit (provision), net of federal (provision) benefit, Percentage		5.53%	(0.31%)	(3.19%)
Research and development credits		3,538	3,177	6,257
Research and development credits, Percentage		(2.92%)	(13.31%)	24.16%
Foreign tax credits		0	574	2,434
Foreign tax credits, Percent		0.00%	(2.41%)	9.39%
Effect of changes in income tax rate applied to net deferred tax assets		(20)	(65)	(1,250)
Effect of changes in income tax rate applied to net deferred tax assets, Percentage		0.02%	0.27%	(4.83%)
Foreign tax rate difference		(13,342)	636	3,218
Foreign tax rate difference, Percentage		11.00%	(2.66%)	12.43%
Change in valuation allowance		135,812	5,890	(40,675)
Change in valuation allowance, Percentage		(112.02%)	(24.67%)	(157.05%)
Repurchase of convertible subordinated notes		0	0	438
Repurchase Of Convertible Subordinated Notes, Percentage		0.00%	0.00%	1.69%
Adjustments to net deferred tax assets		0	2,939	(872)
Adjustments To Net Deferred Tax Assets, Percentage		0.00%	(12.31%)	(3.37%)
Stock-based compensation		(1,309)	(635)	(2,108)
Share-based compensation, Percentage		1.08%	2.66%	(8.14%)
Tax reserve adjustments		(3,928)	(1,482)	(515)
Tax reserve adjustments, Percentage		3.24%	6.21%	(1.99%)
Deemed dividend		(2,751)	(1,122)	(1,749)
Deemed Dividend, Percentage		2.27%	4.70%	(6.75%)
Write-off U.K. gross deferred tax assets		0	(12,699)	0
Write-off U.K. gross deferred tax assets, Percent		0.00%	53.19%	0.00%
Domestic production activities deduction		2,620	0	0
Domestic production activities deduction, Percent		(2.16%)	0.00%	0.00%
Other income tax benefit (expense)		3,586	(164)	(516)
Other income tax benefit (expense), Percentage		(2.95%)	0.69%	(1.99%)
Total	$ 110,000	$ 75,062	$ (11,231)	$ (27,100)
Total, Percentage		(61.91%)	47.05%	(104.64%)