Net Income Per Share (Calculation Of Basic And Diluted Net Income Per Share) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Oct. 26, 2013	Oct. 27, 2012
Earnings Per Share [Abstract]
Net income	$ 1,996	$ 2,092
Weighted Average Shares, Basic (in shares)	5,378	5,301
Weighted Average Number Diluted Shares Outstanding Adjustment	52	33
Weighted-average shares-diluted (in shares)	5,430	5,334
Net income per share-basic	$ 0.37	$ 0.39
Earnings Per Share, Diluted	$ 0.37	$ 0.39
Antidilutive employee share-based awards, excluded	174	438