Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 24, 2016
Federal:
Current	$ 41,425	$ 7,842	$ 7,652
Deferred	(33,819)	5,980	5,043
Federal income tax expense/(benefit)	7,606	13,822	12,695
State:
Current	551	259	990
Deferred	48	2	(138)
State income tax expense/(benefit)	599	261	852
Foreign:
Current	3,986	1,671	2,105
Deferred	1,181	(16)	33
Foreign income tax expense/(benefit)	5,167	1,655	2,138
Provision for income taxes	$ 13,372	$ 15,738	$ 15,685