Net Income per Share (Calculation Of Basic And Diluted Net Income Per Share) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Oct. 25, 2014	Oct. 26, 2013
Earnings Per Share [Abstract]
Net income	$ 1,828	$ 1,996
Weighted-average shares—basic	5,112	5,378
Effect of dilutive potential common shares	44	52
Weighted-average shares—diluted	5,156	5,430
Net income per share—basic	$ 0.36	$ 0.37
Net income per share—diluted	$ 0.35	$ 0.37
Antidilutive employee share-based awards, excluded	114	174