Consolidated Financial Statement Details - Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	Sep. 28, 2019	Sep. 29, 2018
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 95,957	$ 90,403
Accumulated depreciation and amortization	(58,579)	(49,099)
Total property, plant and equipment, net	37,378	41,304
Land and buildings
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	17,085	16,216
Machinery, equipment and internal-use software
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	69,797	65,982
Leasehold improvements
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 9,075	$ 8,205