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		9 Months Ended
	Apr. 30, 2016	Apr. 25, 2015	Apr. 30, 2016	Apr. 25, 2015
Earnings Per Share [Abstract]
Net income	$ 2,349	$ 2,437	$ 7,926	$ 6,662
Weighted-average shares—basic (in shares)	5,032	5,102	5,060	5,110
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements (in shares)	33	46	35	44
Weighted-average shares—diluted (in shares)	5,065	5,148	5,095	5,154
Net income per share—basic	$ 0.47	$ 0.48	$ 1.57	$ 1.30
Net income per share—diluted	$ 0.46	$ 0.47	$ 1.56	$ 1.29
Antidilutive employee share-based awards, excluded (in shares)	75	75	149	156