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		6 Months Ended
	Jan. 25, 2014	Jan. 26, 2013	Jan. 25, 2014	Jan. 26, 2013
Earnings Per Share [Abstract]
Net income	$ 1,429	$ 3,143	$ 3,425	$ 5,235
Weighted Average Shares, Basic (in shares)	5,294	5,318	5,336	5,310
Weighted Average Number Diluted Shares Outstanding Adjustment	33	39	47	34
Weighted-average shares-diluted (in shares)	5,327	5,357	5,383	5,344
Net income per share-basic	$ 0.27	$ 0.59	$ 0.64	$ 0.99
Earnings Per Share, Diluted	$ 0.27	$ 0.59	$ 0.64	$ 0.98
Antidilutive employee share-based awards, excluded	278	324	252	519