Revenue Recognition - Net Sales Disaggregated by Significant Products and Services (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 25, 2021	Sep. 26, 2020	Sep. 28, 2019
Disaggregation of Revenue [Line Items]
Net sales	$ 365,817	$ 274,515	$ 260,174
Revenue recognized that was included in deferred revenue at the beginning of the period	6,700	5,000	5,900
iPhone
Disaggregation of Revenue [Line Items]
Net sales	191,973	137,781	142,381
Mac
Disaggregation of Revenue [Line Items]
Net sales	35,190	28,622	25,740
iPad
Disaggregation of Revenue [Line Items]
Net sales	31,862	23,724	21,280
Wearables, Home and Accessories
Disaggregation of Revenue [Line Items]
Net sales	38,367	30,620	24,482
Services
Disaggregation of Revenue [Line Items]
Net sales	$ 68,425	$ 53,768	$ 46,291