Net Gains or Losses Recognized on Economic Exposures Associated With Foreign Currency Exchange Contracts (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 27, 2014	Dec. 28, 2013
Costs and Expenses
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (losses) on foreign currency denominated assets and liabilities	$ (215)	$ 9
Net gains (losses) on foreign exchange risk management contracts not designated as hedges	205	(22)
Net gains (losses)	(10)	(13)
Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Net gains (losses) on foreign currency denominated assets and liabilities	12	12
Net gains (losses) on foreign exchange risk management contracts not designated as hedges	(12)	(10)
Net gains (losses)	$ 0	$ 2