Condensed Consolidated Financial Statement Details - Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	Dec. 30, 2017	Sep. 30, 2017
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 77,110	$ 75,076
Accumulated depreciation and amortization	(43,431)	(41,293)
Total property, plant and equipment, net	33,679	33,783
Land and buildings
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	14,189	13,587
Machinery, equipment and internal-use software
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	55,479	54,210
Leasehold improvements
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 7,442	$ 7,279