Condensed Consolidated Financial Statement Details - Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	Dec. 28, 2019	Sep. 28, 2019
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 97,990	$ 95,957
Accumulated depreciation and amortization	(60,959)	(58,579)
Total property, plant and equipment, net	37,031	37,378
Land and buildings
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	17,754	17,085
Machinery, equipment and internal-use software
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	70,841	69,797
Leasehold improvements
Property, Plant and Equipment [Line Items]
Gross property, plant and equipment	$ 9,395	$ 9,075