Balance Sheet Details - Property and Equipment Net (Detail) (USD $) In Millions, unless otherwise specified	Oct. 24, 2014	Apr. 25, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,238.5	$ 2,192.5
Accumulated depreciation and amortization	(1,156.8)	(1,083.7)
Property and equipment, net	1,081.7	1,108.8
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	265.7	265.7
Buildings and building improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	605.5	541.7
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	106.5	102.9
Computer, production, engineering and other equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	778.1	753.8
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	376.7	369.1
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	85.3	86.4
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20.7	$ 72.9