Debt - Summary of Cash Flows Associated With Issuance and Maturities of Commercial Paper (Detail) - USD ($) $ in Millions	12 Months Ended
Sep. 24, 2016	Sep. 26, 2015	Sep. 27, 2014
Maturities less than 90 days:
Proceeds from (repayments of) commercial paper, net	$ (869)	$ 5,293
Maturities greater than 90 days:
Proceeds from commercial paper	3,632	3,851
Repayments of commercial paper	(3,160)	(6,953)
Proceeds from (repayments of) commercial paper, net	472	(3,102)
Total change in commercial paper, net	$ (397)	$ 2,191	$ 6,306

The net cash inflow or cash outflow from issuing (borrowing) and repaying commercial paper.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 9
-Subparagraph c
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3098-108585

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- Definition

The cash inflow from a borrowing net of the cash outflow from repayment of a borrowing having initial term of repayment of more than three months but less than one year or one operating cycle (if the normal cycle is more than one year).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

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- Definition

The cash inflow from a borrowing net of the cash outflow from repayment of a borrowing having initial term of repayment within three months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

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-Publisher FASB
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-Publisher FASB
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The cash inflow from a borrowing having initial term of repayment of more than three months but less than one year or one operating cycle (if the normal cycle is more than one year).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6513228

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The cash outflow from a repayment of a borrowing having initial term of repayment of more than three months but less than one year or one operating cycle (if the normal cycle is more than one year).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 15
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-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585

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-Publisher FASB
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-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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