Balance Sheet Detail (Property, Plant and Equipment) (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 25, 2015	Oct. 26, 2014	Oct. 27, 2013
Property, Plant and Equipment, Net
Gross property, plant and equipment	$ 2,946	$ 2,848
Accumulated depreciation	(2,054)	(1,987)
Net property, plant and equipment	892	861
Depreciation	185	191	$ 211
Land and improvements
Property, Plant and Equipment, Net
Gross property, plant and equipment	157	156
Building and improvements
Property, Plant and Equipment, Net
Gross property, plant and equipment	$ 1,247	1,227
Building and improvements | Minimum
Property, Plant and Equipment, Net
Useful life	3 years
Building and improvements | Maximum
Property, Plant and Equipment, Net
Useful life	30 years
Demonstration and manufacturing equipment
Property, Plant and Equipment, Net
Gross property, plant and equipment	$ 920	829
Demonstration and manufacturing equipment | Minimum
Property, Plant and Equipment, Net
Useful life	3 years
Demonstration and manufacturing equipment | Maximum
Property, Plant and Equipment, Net
Useful life	5 years
Furniture, fixtures and other equipment
Property, Plant and Equipment, Net
Gross property, plant and equipment	$ 574	575
Furniture, fixtures and other equipment | Minimum
Property, Plant and Equipment, Net
Useful life	3 years
Furniture, fixtures and other equipment | Maximum
Property, Plant and Equipment, Net
Useful life	15 years
Construction in progress
Property, Plant and Equipment, Net
Gross property, plant and equipment	$ 48	$ 61