Condensed Consolidated Financial Statement Details - Other Income/(Expense), Net (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest and dividend income	$ 1,418	$ 1,327	$ 4,375	$ 3,833
Interest expense	(846)	(602)	(2,372)	(1,657)
Other income/(expense), net	100	(185)	(301)	(228)
Total other income/(expense), net	$ 672	$ 540	$ 1,702	$ 1,948