Summary of Cash Flows Associated With Issuance and Maturities of Commercial Paper (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Dec. 27, 2014	Dec. 28, 2013
Maturities less than 90 days:
Proceeds from (repayments of) commercial paper, net	$ 62
Maturities greater than 90 days:
Proceeds from commercial paper	197
Repayments of commercial paper	(2,668)
Maturities greater than 90 days, net	(2,471)
Total repayments of commercial paper, net	$ (2,409)	$ 0

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

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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).

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

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

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-Name Accounting Standards Codification

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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).

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

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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).

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