Comprehensive Income - Pre-tax Amounts Reclassified from AOCI into the Condensed Consolidated Statements of Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 29, 2018	Dec. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total cost of sales	$ 52,279	$ 54,381
Other income/(expense), net	(560)	(756)
Total amounts reclassified from AOCI	(23,906)	(27,030)
Reclassifications out of AOCI
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total amounts reclassified from AOCI	132	7
Reclassifications out of AOCI | Unrealized (gains)/losses on derivative instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total amounts reclassified from AOCI	85	123
Reclassifications out of AOCI | Unrealized (gains)/losses on derivative instruments | Foreign exchange contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total net sales	63	184
Total cost of sales	(375)	(27)
Other income/(expense), net	396	(33)
Reclassifications out of AOCI | Unrealized (gains)/losses on derivative instruments | Interest rate contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income/(expense), net	1	(1)
Reclassifications out of AOCI | Unrealized (gains)/losses on marketable securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income/(expense), net	$ 47	$ (116)