Segment Information and Geographic Data - Summary Information by Reportable Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Net sales	$ 53,809	$ 53,265	$ 196,134	$ 202,695
Operating income	11,544	12,612	48,305	54,780
Americas
Segment Reporting Information [Line Items]
Net sales	25,056	24,542	87,592	84,576
Operating income	7,442	7,496	26,329	26,580
Europe
Segment Reporting Information [Line Items]
Net sales	11,925	12,138	45,342	47,038
Operating income	3,687	3,892	14,371	15,044
Greater China
Segment Reporting Information [Line Items]
Net sales	9,157	9,551	32,544	40,531
Operating income	3,221	3,414	12,142	15,285
Japan
Segment Reporting Information [Line Items]
Net sales	4,082	3,867	16,524	16,572
Operating income	1,795	1,765	7,199	7,193
Rest of Asia Pacific
Segment Reporting Information [Line Items]
Net sales	3,589	3,167	14,132	13,978
Operating income	$ 1,155	$ 1,127	$ 4,811	$ 4,980