Impact of Adoption on the Condensed Consolidated Statement of Income (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 29, 2018	Dec. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle
Revenues	$ 15,303	$ 15,351
Costs and Expenses	(11,885)	(11,558)
Income Taxes	645	(728)
Net income	2,786	$ 4,473
Calculated under Revenue Guidance in Effect before Topic 606
New Accounting Pronouncements or Change in Accounting Principle
Revenues	15,109
Costs and Expenses	(11,806)
Income Taxes	(619)
Net income	2,697
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606
New Accounting Pronouncements or Change in Accounting Principle
Revenues	194
Costs and Expenses	(79)
Income Taxes	(26)
Net income	$ 89