Net Income Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 27, 2013	Oct. 28, 2012	Jul. 29, 2012	Apr. 29, 2012	Jan. 29, 2012	Oct. 30, 2011	Jul. 31, 2011	May 01, 2011	Jan. 27, 2013	Jan. 29, 2012	Jan. 30, 2011
Numerator:
Net income	$ 173,973	$ 209,080	$ 119,046	$ 60,437	$ 116,025	$ 178,273	$ 151,573	$ 135,219	$ 562,536	$ 581,090	$ 253,146
Denominator:
Denominator for basic net income per share, weighted average shares (in shares)									619,324,000	603,646,000	575,177,000
Effect of dilutive securities:
Equity awards outstanding (in shares)									5,633,000	12,725,000	13,507,000
Denominator for diluted net income per share, weighted average shares (in shares)									624,957,000	616,371,000	588,684,000
Net income per share:
Basic net income per share	$ 0.28	$ 0.34	$ 0.19	$ 0.10	$ 0.19	$ 0.29	$ 0.25	$ 0.23	$ 0.91	$ 0.96	$ 0.44
Diluted net income per share	$ 0.28	$ 0.33	$ 0.19	$ 0.10	$ 0.19	$ 0.29	$ 0.25	$ 0.22	$ 0.90	$ 0.94	$ 0.43
Anti-dilutive common equivalent shares from stock options and RSUs (in shares)									26,784,208	22,617,213	24,646,398