Condensed Consolidated Financial Statement Details - Other Income/(Expense), Net (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 29, 2018	Dec. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest and dividend income	$ 1,307	$ 1,452
Interest expense	(890)	(734)
Other income, net	143	38
Total other income/(expense), net	$ 560	$ 756

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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Amount of income (expense) related to nonoperating activities, classified as other.

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