Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Apr. 26, 2013	Apr. 27, 2012	Apr. 29, 2011	Apr. 30, 2010
Operating Loss Carryforwards [Line Items]
Deferred tax assets, increase/decrease in valuation allowance	$ 7,400,000	$ (13,100,000)
Valuation allowance attributable to foreign tax credit carryforwards		7,100,000
Unrecognized tax benefits	189,600,000	161,000,000	133,300,000	134,500,000
Unrecognized tax benefits included in other long-term liabilities	134,700,000
Unrecognized tax benefits that would affect provision for income taxes	118,700,000
Tax penalties and interest on unrecognized tax benefits	1,200,000	600,000	200,000
Accrued tax penalties and interest on unrecognized tax benefits	2,800,000	1,600,000
Resolution of income tax examinations	100,000	7,300,000	(21,100,000)
Tax benefit from holiday			6,300,000
Tax benefit effect on per share earnings			$ 0.02
Accumulated remitted earnings from foreign subsidiaries	2,500,000,000
Estimated unrecognized deferred tax liability on unremitted earnings of foreign subsidiaries	757,600,000
Convertible Notes Payable
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits				28,900,000
Minimum
Operating Loss Carryforwards [Line Items]
Operating loss carry forwards, expiration dates	2014
Maximum
Operating Loss Carryforwards [Line Items]
Operating loss carry forwards, expiration dates	2033
Federal Income Tax
Operating Loss Carryforwards [Line Items]
Operating loss carry forwards	43,400,000
Tax credit carry forward amount	155,100,000
State and Local Income Tax
Operating Loss Carryforwards [Line Items]
Operating loss carry forwards	83,500,000
Tax credit carry forward amount	125,600,000
Additional Paid-in Capital
Operating Loss Carryforwards [Line Items]
Unrecognized tax benefits	$ 169,500,000