Segment Geographic and Significant Customer Information - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Apr. 25, 2014	Jan. 24, 2014	Oct. 25, 2013	Jul. 26, 2013	Apr. 26, 2013	Jan. 25, 2013	Oct. 26, 2012	Jul. 27, 2012	Apr. 25, 2014 Segment	Apr. 26, 2013 Segment	Apr. 27, 2012 Segment
Segment Reporting Information [Line Items]
Number of industry segment									1	1	1
Net revenues	$ 1,649.0	$ 1,610.0	$ 1,549.9	$ 1,516.2	$ 1,716.5	$ 1,630.1	$ 1,541.2	$ 1,444.6	$ 6,325.1	$ 6,332.4	$ 6,233.2
United States
Segment Reporting Information [Line Items]
Net revenues									3,130.9	3,152.7	3,027.8
Germany
Segment Reporting Information [Line Items]
Net revenues											$ 632.6