Selected Quarterly Financial Data Unaudited - Selected Quarterly Financial Data (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Apr. 26, 2013	Jan. 25, 2013	Oct. 26, 2012	Jul. 27, 2012	Apr. 27, 2012	Jan. 27, 2012	Oct. 28, 2011	Jul. 29, 2011	Apr. 26, 2013	Apr. 27, 2012	Apr. 29, 2011
Quarterly Financial Information [Line Items]
Net revenues	$ 1,716.5	$ 1,630.1	$ 1,541.2	$ 1,444.6	$ 1,702.5	$ 1,565.5	$ 1,507.0	$ 1,458.2	$ 6,332.4	$ 6,233.2	$ 5,122.6
Total cost of revenues	684.3	665.2	627.3	594.5	707.5	657.0	594.0	561.3	2,571.3	2,519.8	1,793.9
Gross profit	1,032.2	964.9	913.9	850.1	995.0	908.5	913.0	896.9	3,761.1	3,713.4	3,328.7
Income before income taxes	188.9	175.8	127.7	74.2	214.5	146.9	183.9	167.1	566.6	712.4	794.1
Provision for income taxes	15.1	17.7	18.1	10.4	33.8	27.3	18.3	27.6	61.3	107.0	121.0
Net Income	$ 173.8	$ 158.1	$ 109.6	$ 63.8	$ 180.7	$ 119.6	$ 165.6	$ 139.5	$ 505.3	$ 605.4	$ 673.1
Net income per share, basic	$ 0.48	$ 0.44	$ 0.30	$ 0.17	$ 0.50	$ 0.33	$ 0.46	$ 0.38	$ 1.40	$ 1.66	$ 1.87
Net income per share, diluted	$ 0.47	$ 0.43	$ 0.30	$ 0.17	$ 0.47	$ 0.32	$ 0.44	$ 0.34	$ 1.37	$ 1.58	$ 1.71