Gross Fair Value of Derivative Positions (Details) - USD ($) $ in Millions	Apr. 01, 2017	Oct. 01, 2016
Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	$ 440	$ 406
Derivative Asset, Counterparty Netting Offset	(266)	(241)
Derivative Asset, Collateral, Obligation to Return Cash, Offset	(68)	(77)
Net derivative positions	106	88
Current Assets | Derivatives designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	304	278
Current Assets | Derivatives designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	0	0
Current Assets | Derivatives designated as hedges | Other Derivative
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	4	3
Current Assets | Derivatives not designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	132	125
Current Assets | Derivatives not designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	0
Other Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	253	328
Derivative Asset, Counterparty Netting Offset	(149)	(199)
Derivative Asset, Collateral, Obligation to Return Cash, Offset	(24)	(44)
Net derivative positions	80	85
Other Assets | Derivatives designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	204	191
Other Assets | Derivatives designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	15	132
Other Assets | Derivatives designated as hedges | Other Derivative
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	2	3
Other Assets | Derivatives not designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	32	2
Other Assets | Derivatives not designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	0
Other Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(399)	(359)
Derivative Liability, Counterparty netting offset	309	316
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	(38)	(7)
Net derivative positions	(52)	(36)
Other Accrued Liabilities | Derivatives designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(121)	(209)
Other Accrued Liabilities | Derivatives designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(142)	(13)
Other Accrued Liabilities | Derivatives designated as hedges | Other Derivative
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(2)	(4)
Other Accrued Liabilities | Derivatives not designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(134)	(133)
Other Accrued Liabilities | Derivatives not designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	0
Other Long-Term Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(145)	(168)
Derivative Liability, Counterparty netting offset	106	124
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Net derivative positions	(39)	(44)
Other Long-Term Liabilities | Derivatives designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(124)	(163)
Other Long-Term Liabilities | Derivatives designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	0	0
Other Long-Term Liabilities | Derivatives designated as hedges | Other Derivative
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	0	0
Other Long-Term Liabilities | Derivatives not designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	0	$ (5)
Other Long-Term Liabilities | Derivatives not designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	$ (21)