Balance Sheet Detail (Property, Plant and Equipment) (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2016	Oct. 25, 2015
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 2,978	$ 2,946
Accumulated depreciation	(2,070)	(2,054)
Net property, plant and equipment	908	892
Land and improvements [Member]
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	157	157
Building and improvements [Member]
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 1,249	1,247
Building and improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Useful life	3 years
Building and improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Useful life	30 years
Demonstration and manufacturing equipment [Member]
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 927	920
Demonstration and manufacturing equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Useful life	3 years
Demonstration and manufacturing equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Useful life	5 years
Furniture, fixtures and other equipment [Member]
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 586	574
Furniture, fixtures and other equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Useful life	3 years
Furniture, fixtures and other equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Useful life	15 years
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 59	$ 48