Employee Benefit Plans (Summary Of Stock Option Activity) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Oct. 26, 2013	Jul. 27, 2013
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Beginning balance, Number Outstanding (in shares)	276	520
Share Based Compensation Arrangement By Share Based Payment Award Options Assumed From Acquisitions In Period	3	10
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)	(24)	(154)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	(6)	(100)
Ending balance, Number Outstanding (in shares)	249	276
Weighted-average exercise price per share, beginning balance	$ 24.44	$ 22.68
Share Based Compensation Arrangement By Share Based Payment Award Options Assumed From Acquisition In Period Weighted Average Exercise Price	$ 6.03	$ 0.77
Exercised, weighted-average exercise price per share	$ 19.01	$ 18.51
Canceled/forfeited/expired, weighted-average exercise price per share	$ 29.16	$ 22.18
Weighted-average exercise price per share, beginning balance	$ 24.62	$ 24.44