Segment Information and Geographic Data - Long-Lived Assets (Details) - USD ($) $ in Millions	Sep. 25, 2021	Sep. 26, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 39,440	$ 36,766
U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	28,203	25,890
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	7,521	7,256
Other countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 3,716	$ 3,620