Net Income per Share (Calculation Of Basic And Diluted Net Income Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Oct. 24, 2015	Oct. 25, 2014
Earnings Per Share [Abstract]
Net income	$ 2,430	$ 1,828
Weighted-average shares—basic (in shares)	5,080	5,112
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements (in shares)	33	44
Weighted-average shares—diluted (in shares)	5,113	5,156
Net income per share—basic	$ 0.48	$ 0.36
Net income per share—diluted	$ 0.48	$ 0.35
Antidilutive employee share-based awards, excluded (in shares)	86	114