Property, Plant and Equipment (Details) - USD ($) $ in Millions	Mar. 25, 2016	Sep. 25, 2015
Property, Plant and Equipment:
Accumulated depreciation	$ (2,459)	$ (2,527)
Property, plant and equipment, net	1,189	1,177
Land
Property, Plant and Equipment:
Property, plant and equipment	33	33
Buildings
Property, Plant and Equipment:
Property, plant and equipment	429	405
Subscriber systems
Property, Plant and Equipment:
Property, plant and equipment	1,802	1,933
Machinery and equipment
Property, Plant and Equipment:
Property, plant and equipment	1,281	1,252
Construction in progress
Property, Plant and Equipment:
Property, plant and equipment	$ 103	$ 81