Employee Benefit Plans (Summary Of Share-Based Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 25, 2015	Jul. 26, 2014	Jul. 27, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 1,440	$ 1,348	$ 1,120
Income tax benefit for share-based compensation	373	324	285
Cost of sales—product
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	50	45	40
Cost of sales—service
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	157	150	138
Cost of sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	207	195	178
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	448	411	286
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	559	549	484
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	228	198	175
Restructuring and other charges
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Granted, Value, Share-based Compensation, Forfeited	(2)	(5)	(3)
Operating expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 1,233	$ 1,153	$ 942