Comprehensive Income - Pre-tax Amounts Reclassified from AOCI into Consolidated Statements of Operations (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Sep. 29, 2018	Sep. 30, 2017	Sep. 24, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net sales	$ (62,900)	$ (53,265)	$ (61,137)	$ (88,293)	$ (52,579)	$ (45,408)	$ (52,896)	$ (78,351)	$ (265,595)	$ (229,234)	$ (215,639)
Cost of sales									163,756	141,048	131,376
Other income/(expense), net									(2,005)	(2,745)	(1,348)
Total amounts reclassified from AOCI									(72,903)	(64,089)	$ (61,372)
Reclassifications out of AOCI
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total amounts reclassified from AOCI									466	(2,051)
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									486	(1,952)
Reclassifications out of AOCI | Unrealized (gains)/losses on derivative instruments | Foreign exchange contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net sales									214	(662)
Cost of sales									(70)	(654)
Other income/(expense), net									344	(638)
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									(2)	2
Reclassifications out of AOCI | Unrealized (gains)/losses on marketable securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income/(expense), net									$ (20)	$ (99)