Net Income per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended												12 Months Ended
	Apr. 29, 2011		Jan. 28, 2011		Oct. 29, 2010		Jul. 30, 2010		Apr. 30, 2010	Jan. 29, 2010	Oct. 30, 2009	Jul. 31, 2009	Apr. 29, 2011	Apr. 30, 2010	Apr. 24, 2009
Net income	$ 160.6	[1]	$ 186.4	[2]	$ 175.4	[2]	$ 150.7	[2]	$ 145.1	$ 107.9	$ 95.7	$ 51.7	$ 673.1	$ 400.4	$ 64.6
Weighted average common shares outstanding													360.9	339.7	330.4
Weighted average common shares outstanding subject to repurchase													0	(0.1)	(0.1)
Shares used in basic computation													360.9	339.6	330.3
Weighted average common shares outstanding subject to repurchase													0	0.1	0.1
Dilutive potential shares related to employee equity award plans													14.6	13.2	4.2
Dilutive impact of assumed conversion of Notes													12.7	0.3	0
Dilutive impact of warrants													5.5	0	0
Shares used in diluted computation													393.7	353.2	334.6
Basic	$ 0.44	[1]	$ 0.51	[2]	$ 0.49	[2]	$ 0.43	[2]	$ 0.42	$ 0.32	$ 0.28	$ 0.15	$ 1.87	$ 1.18	$ 0.20
Diluted	$ 0.40	[1]	$ 0.46	[2]	$ 0.45	[2]	$ 0.40	[2]	$ 0.40	$ 0.30	$ 0.27	$ 0.15	$ 1.71	$ 1.13	$ 0.19
Percentage of reduction in notes when stock price increases													80.00%
Debt instrument convertible conversion price	$ 31.85												$ 31.85
Options and Restricted Stock Units [Member]
Options and RSUs													2.6	19.3	61.1

[1] As a result of the adoption of new revenue recognition accounting standards, fourth quarter fiscal 2011 net revenues and net income were higher by $48.2 million and $19.4 million, respectively

[2] The amounts previously reported in our Quarterly Reports on Form 10-Q for fiscal 2011 have been adjusted to reflect the retrospective adoption of new revenue recognition accounting standards, which is discussed more fully in Note 2. The impact from the adoption was as follows (in millions, except per share amounts):