Revenue - Net Sales Disaggregated by Significant Products and Services (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 26, 2022	Mar. 27, 2021	Mar. 26, 2022	Mar. 27, 2021
Disaggregation of Revenue [Line Items]
Net sales	$ 97,278	$ 89,584	$ 221,223	$ 201,023
Revenue recognized that was included in deferred revenue at the beginning of the period	3,000	2,700	4,800	4,100
iPhone
Disaggregation of Revenue [Line Items]
Net sales	50,570	47,938	122,198	113,535
Mac
Disaggregation of Revenue [Line Items]
Net sales	10,435	9,102	21,287	17,777
iPad
Disaggregation of Revenue [Line Items]
Net sales	7,646	7,807	14,894	16,242
Wearables, Home and Accessories
Disaggregation of Revenue [Line Items]
Net sales	8,806	7,836	23,507	20,807
Services
Disaggregation of Revenue [Line Items]
Net sales	$ 19,821	$ 16,901	$ 39,337	$ 32,662