Balance Sheet Details (Details) - USD ($) $ in Millions	Jul. 29, 2017	Jul. 30, 2016	Jul. 25, 2015
Inventories:
Raw materials	$ 289	$ 91
Work in process	1	0
Finished goods:
Distributor inventory and deferred cost of sales	451	457
Manufactured finished goods	552	415
Total finished goods	1,003	872
Service-related spares	300	236
Demonstration systems	23	18
Total	1,616	1,217
Gross property and equipment:
Land, buildings, and building and leasehold improvements	4,926	4,778
Computer equipment and related software	1,258	1,288
Production, engineering, and other equipment	5,707	5,658
Operating lease assets	356	296
Furniture and fixtures	572	543
Total gross property and equipment	12,819	12,563
Less: accumulated depreciation and amortization	(9,497)	(9,057)
Total	3,322	3,506	$ 3,332
Deferred Revenue Arrangement [Line Items]
Deferred revenue:	18,494	16,472
Current	10,821	10,155
Noncurrent	7,673	6,317
Service
Deferred Revenue Arrangement [Line Items]
Deferred revenue:	11,302	10,621
Product:
Deferred Revenue Arrangement [Line Items]
Deferred revenue:	7,192	5,851
Product: | Deferred revenue related to recurring software and subscription offers
Deferred Revenue Arrangement [Line Items]
Deferred revenue:	4,971	3,308
Product: | Other product deferred revenue
Deferred Revenue Arrangement [Line Items]
Deferred revenue:	$ 2,221	$ 2,543