Consolidated Financial Statement Details - Other Income/(Expense), Net (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest and dividend income	$ 3,763	$ 4,961	$ 5,686
Interest expense	(2,873)	(3,576)	(3,240)
Other income/(expense), net	(87)	422	(441)
Total other income/(expense), net	$ 803	$ 1,807	$ 2,005

Amount of the cost of borrowed funds accounted for as interest expense.

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Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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