Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Federal:
Current	$ 6,306	$ 6,384	$ 41,425
Deferred	(3,619)	(2,939)	(33,819)
Federal income tax expense/(benefit)	2,687	3,445	7,606
State:
Current	455	475	551
Deferred	21	(67)	48
State income tax expense/(benefit)	476	408	599
Foreign:
Current	3,134	3,962	3,986
Deferred	3,383	2,666	1,181
Foreign income tax expense/(benefit)	6,517	6,628	5,167
Provision for income taxes	$ 9,680	$ 10,481	$ 13,372