Pre-Tax Effect of Derivative Instruments Designated as Cash Flow, Net Investment and Fair Value Hedges (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Dec. 27, 2014	Dec. 28, 2013
Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gains/(Losses) Recognized in OCI - Effective Portion	$ 2,497	$ 285
Gains/(Losses) Reclassified from AOCI into Net Income - Effective Portion	663	(78)
Cash flow hedges \| Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains/(Losses) Recognized in OCI - Effective Portion	2,585	264
Gains/(Losses) Reclassified from AOCI into Net Income - Effective Portion	762	(74)
Cash flow hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains/(Losses) Recognized in OCI - Effective Portion	(88)	21
Gains/(Losses) Reclassified from AOCI into Net Income - Effective Portion	(99)	(4)
Net investment hedges \| Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains/(Losses) Recognized in OCI - Effective Portion	118	24
Gains/(Losses) Reclassified from AOCI into Net Income - Effective Portion	0	0
Fair Value Hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains/(Losses) on Derivative Instruments	117	0
Gains/(Losses) Related to Hedged Items	$ (117)	$ 0

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

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-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5618551-113959

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

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-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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