Comprehensive Income - Pre-tax Amounts Reclassified from AOCI into Condensed Consolidated Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2016	Dec. 26, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue	$ (78,351)	$ (75,872)
Cost of sales	48,175	45,449
Other income/(expense), net	(821)	(402)
Income before provision for income taxes	(24,180)	(24,573)
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before provision for income taxes	548	(438)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains/Losses on Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before provision for income taxes	517	(511)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains/Losses on Derivative Instruments | Foreign exchange contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue	(101)	(329)
Cost of sales	13	(306)
Other income/(expense), net	604	120
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains/Losses on Derivative Instruments | Interest rate contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income/(expense), net	1	4
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains/Losses on Marketable Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income/(expense), net	$ 31	$ 73