Notional Amounts of Outstanding Derivative Instruments and Credit Risk Amounts Associated with Outstanding or Unsettled Derivative Instruments (Detail) (USD $) In Millions, unless otherwise specified	Mar. 28, 2015	Sep. 27, 2014
Derivatives Designated as Hedging Instruments | Foreign exchange contracts
Derivative [Line Items]
Notional Amount	$ 37,855	$ 42,945
Credit Risk	3,045	1,333
Derivatives Designated as Hedging Instruments | Interest rate contracts
Derivative [Line Items]
Notional Amount	18,013	12,000
Credit Risk	329	89
Not Designated as Hedging Instrument | Foreign exchange contracts
Derivative [Line Items]
Notional Amount	27,486	38,510
Credit Risk	$ 86	$ 222