Stock Activity Related to RSUs Vested (Detail) - Restricted Stock Units - USD ($) $ in Millions	12 Months Ended
Sep. 29, 2017	Sep. 30, 2016
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Tax benefits related to RSUs vested	$ 1	$ 162
Intrinsic value of RSUs vested	$ 3,631	$ 3,847

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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