New Accounting Pronouncements New Accounting Pronouncements - Additional Details (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation		$ 207	$ 313
Adjustments to Income Tax Expense, Income Tax Benefit from Share-based Compensation	$ 125
Operating Leases, Future Minimum Payments Due	3,348
Accounting Standards Update 2016-18
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted Cash and Cash Equivalents		300	200
Accounting Standards Update 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation		200	300
Payments Related to Tax Withholding for Share-based Compensation	200	200	$ 300
Adjustments to Income Tax Expense, Income Tax Benefit from Share-based Compensation	100
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Leases, Future Minimum Payments Due	$ 3,300	$ 3,100