Segment Information and Geographic Data - Summary Information by Operating Segment (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2016	Dec. 26, 2015
Segment Reporting Information [Line Items]
Net sales	$ 78,351	$ 75,872
Operating income	23,359	24,171
Americas
Segment Reporting Information [Line Items]
Net sales	31,968	29,325
Operating income	10,494	10,018
Europe
Segment Reporting Information [Line Items]
Net sales	18,521	17,932
Operating income	5,736	5,779
Greater China
Segment Reporting Information [Line Items]
Net sales	16,233	18,373
Operating income	6,176	7,576
Japan
Segment Reporting Information [Line Items]
Net sales	5,766	4,794
Operating income	2,673	2,240
Rest of Asia Pacific
Segment Reporting Information [Line Items]
Net sales	5,863	5,448
Operating income	$ 2,229	$ 2,032