Net Gains or Losses Recognized on Economic Exposures Associated With Foreign Currency Exchange Contracts (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Costs and Expenses
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (losses) on foreign currency denominated assets and liabilities	$ (175)	$ 148	$ (94)	$ 25
Net gains (losses) on foreign exchange risk management contracts not designated as hedges	164	(144)	73	(26)
Net gains (losses)	(11)	4	(21)	(1)
Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (losses) on foreign currency denominated assets and liabilities	28	(7)	55	(3)
Net gains (losses) on foreign exchange risk management contracts not designated as hedges	(34)	6	(62)	2
Net gains (losses)	(6)	(1)	(7)	(1)
Income Taxes
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (losses) on foreign currency denominated assets and liabilities	35	4	23	16
Net gains (losses) on foreign exchange risk management contracts not designated as hedges	(31)	21	(15)	4
Net gains (losses)	$ 4	$ 25	$ 8	$ 20