Segment Information and Major Customers (Summary Of Net Revenue For Groups Of Similar Products And Services) (Details) - USD ($) $ in Millions		12 Months Ended
		Jul. 30, 2016	Jul. 25, 2015	Jul. 26, 2014
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		$ 49,247	$ 49,161	$ 47,142
Switching
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		14,746	14,740	14,001
NGN Routing
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		7,408	7,704	7,606
Collaboration
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		4,352	4,004	3,817
Data Center
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		3,365	3,219	2,640
Wireless
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		2,625	2,542	2,293
Service Provider Video
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	[1]	2,424	3,555	3,969
Security
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		1,969	1,747	1,566
Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		365	239	280
Product:
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		37,254	37,750	36,172
Service
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		$ 11,993	$ 11,411	$ 10,970

[1] (1) During the second quarter of fiscal 2016, the Company completed the sale of our SP Video CPE Business. As a result, revenue from this portion of the Service Provider Video product category will not recur in future periods. SP Video CPE Business revenue was $504 million, $1,846 million, and $2,240 million for fiscal 2016, 2015 and 2014, respectively.