Balance Sheet Details - Property and Equipment Net (Detail) (USD $) In Millions, unless otherwise specified	Jul. 25, 2014	Apr. 25, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,222.4	$ 2,192.5
Accumulated depreciation and amortization	(1,124.4)	(1,083.7)
Property and equipment, net	1,098.0	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	605.7	541.7
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	103.9	102.9
Computer, production, engineering and other equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	768.3	753.8
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	376.5	369.1
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	88.3	86.4
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 14.0	$ 72.9