Balance Sheet Details - Property and Equipment Net (Detail) (USD $) In Millions, unless otherwise specified	Jan. 24, 2014	Apr. 26, 2013
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,244.3	$ 2,139.3
Accumulated depreciation and amortization	(1,115.7)	(968.4)
Property and equipment, net	1,128.6	1,170.9
Land and land improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	265.7	265.5
Buildings and building improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	540.6	534.8
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	102.3	100.3
Computer, production, engineering and other equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	759.0	714.0
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	429.4	422.6
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	86.1	82.2
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 61.2	$ 19.9