Segment Information and Geographic Data - Summary Information by Reportable Segment (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Segment Reporting Information [Line Items]
Net sales	$ 64,698	$ 59,685	$ 58,313	$ 91,819	$ 64,040	$ 53,809	$ 58,015	$ 84,310	$ 274,515	$ 260,174	$ 265,595
Operating income									66,288	63,930	70,898
Americas
Segment Reporting Information [Line Items]
Net sales									124,556	116,914	112,093
Operating income									37,722	35,099	34,864
Europe
Segment Reporting Information [Line Items]
Net sales									68,640	60,288	62,420
Operating income									22,170	19,195	19,955
Greater China
Segment Reporting Information [Line Items]
Net sales									40,308	43,678	51,942
Operating income									15,261	16,232	19,742
Japan
Segment Reporting Information [Line Items]
Net sales									21,418	21,506	21,733
Operating income									9,279	9,369	9,500
Rest of Asia Pacific
Segment Reporting Information [Line Items]
Net sales									19,593	17,788	17,407
Operating income									$ 6,808	$ 6,055	$ 6,181