Gross Fair Value of Derivative Positions (Details) - USD ($) $ in Millions	Jul. 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	$ 344	$ 406
Derivative Asset, Counterparty Netting Offset	(252)	(241)
Derivative Asset, Collateral, Obligation to Return Cash, Offset	(45)	(77)
Net derivative positions	47	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	207	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	2	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	135	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	166	328
Derivative Asset, Counterparty Netting Offset	(112)	(199)
Derivative Asset, Collateral, Obligation to Return Cash, Offset	(10)	(44)
Net derivative positions	44	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	155	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	10	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	1	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	0	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 Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(387)	(359)
Derivative Liability, Counterparty netting offset	252	316
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	(11)	(7)
Net derivative positions	(124)	(36)
Other Current 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	(120)	(209)
Other Current 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	(100)	(13)
Other Current 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 Current 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	(165)	(133)
Other Current 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	(148)	(168)
Derivative Liability, Counterparty netting offset	112	124
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Net derivative positions	(36)	(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	(120)	(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	(9)	$ (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	$ (19)

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, and obligation to return cash collateral under master netting arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
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The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that in accordance with the entity's accounting policy were offset against collateral under a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-Section 50
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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 50
-Paragraph 3
-Subparagraph (b)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226003-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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