Income Taxes (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Mar. 30, 2013	Mar. 31, 2012	Mar. 26, 2011
Income Taxes [Line Items]
Decrease in valuation allowance		$ 5,800,000	$ 39,300,000
Federal net operating loss carryforwards		177,100,000
Net operating loss included in deferred tax assets	105,220,000	28,162,000	105,220,000
Tax effected deferred tax asset		19,900,000
Excess stock deductions		120,300,000
Undistributed earnings in non-U.S subsidiaries		228,000
Unrecognized deferred tax liability		81,000
Provision (benefit) for income taxes	39,500,000	64,592,000	(8,000,000)	(119,289,000)
Federal [Member]
Income Taxes [Line Items]
Net operating loss included in deferred tax assets		56,800,000
Section 382 Of Internal Revenue Code [Member]
Income Taxes [Line Items]
Net operating loss included in deferred tax assets		20,900,000
Non-U.S [Member]
Income Taxes [Line Items]
Net operating loss carryforwards		2,000,000
State [Member]
Income Taxes [Line Items]
Net operating loss carryforwards		101,600,000
Maximum [Member] | Federal [Member]
Income Taxes [Line Items]
Net operating loss carryforward expirations		2033
Maximum [Member] | State [Member]
Income Taxes [Line Items]
Net operating loss carryforward expirations		2029
Minimum [Member] | Federal [Member]
Income Taxes [Line Items]
Net operating loss carryforward expirations		2019
Minimum [Member] | State [Member]
Income Taxes [Line Items]
Net operating loss carryforward expirations		2014
Research Tax Credit Carryforward [Member] | Federal [Member]
Income Taxes [Line Items]
Tax credit carryforward		22,500,000
Provision (benefit) for income taxes		(4,200,000)
Research Tax Credit Carryforward [Member] | State [Member]
Income Taxes [Line Items]
Tax credit carryforward		14,500,000
Tax credit carryforward subject to expiration		2,800,000
Tax credit carryforward not subject to expiration		$ 11,700,000
Research Tax Credit Carryforward [Member] | Maximum [Member] | Federal [Member]
Income Taxes [Line Items]
Net operating loss carryforward expirations		2033
Research Tax Credit Carryforward [Member] | Maximum [Member] | State [Member]
Income Taxes [Line Items]
Net operating loss carryforward expirations		2027
Research Tax Credit Carryforward [Member] | Minimum [Member] | Federal [Member]
Income Taxes [Line Items]
Net operating loss carryforward expirations		2014
Research Tax Credit Carryforward [Member] | Minimum [Member] | State [Member]
Income Taxes [Line Items]
Net operating loss carryforward expirations		2022