Employee Benefit Plans (Summary Of Share-Based Compensation Expense) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 25, 2014	Jan. 26, 2013	Jan. 25, 2014	Jan. 26, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	$ 347	$ 302	$ 656	$ 608
Income tax benefit for employee share-based compensation expense	82	80	160	159
Cost Of Sales Product
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	12	11	22	21
Cost Of Sales-Service
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	40	36	73	71
Cost of Sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	52	47	95	92
Operating Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	295	255	561	516
Research And Development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	108	72	200	156
Sales And Marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	141	135	264	265
General And Administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	47	48	101	98
Restructuring And Other Charges
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Value, Share-based Compensation, Forfeited	$ (1)	$ 0	$ (4)	$ (3)