Employee Benefit Plans (Summary Of Share-Based Compensation Expense) (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 27, 2018	Oct. 28, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 408	$ 398
Income tax benefit for share-based compensation	165	175
Share-based compensation expense in cost of sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	56	57
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	130	136
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	137	135
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	62	64
Restructuring and other charges
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	23	6
Share-based compensation expense in operating expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	352	341
Product | Share-based compensation expense in cost of sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	23	23
Service | Share-based compensation expense in cost of sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 33	$ 34