Segment Information and Geographic Data - Reconciliation of Segment Operating Income to Condensed Consolidated Statements of Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 01, 2017	Mar. 26, 2016	Apr. 01, 2017	Mar. 26, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income	$ 14,097	$ 13,987	$ 37,456	$ 38,158
Research and development expense	(2,776)	(2,511)	(5,647)	(4,915)
Operating segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income	18,089	17,561	45,397	45,206
Segment reconciling items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Research and development expense	(2,776)	(2,511)	(5,647)	(4,915)
Corporate non-segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Other corporate expenses, net	$ (1,216)	$ (1,063)	$ (2,294)	$ (2,133)