Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 29, 2018	Oct. 02, 2021	Oct. 03, 2020	Sep. 28, 2019
Income Taxes [Line Items]
Gross unrecognized tax benefits that would reduce income tax expense and effective tax rate, if recognized		$ 2,000	$ 2,100	$ 2,400
Accrued interest and penalties related to unrecognized tax benefits		1,000	1,100	1,000
Additional accrued interest related to unrecognized tax benefits		191	211	802
Reductions in accrued interest as a result of audit settlements and other prior-year adjustments		256	101	96
Unrecognized tax benefits, reasonably possible reduction due to payments for or resolution of open tax matters		400
Adjustments to Income Tax Expense, Income Tax Benefit from Share-based Compensation		$ 135	$ 64	$ 41
Accounting Standards Update 2016-16
Income Taxes [Line Items]
Impact of New Accounting Pronouncement on Retained Earnings	$ 200