Reconciliation of Weighted Average Number of Common and Common Equivalent Shares Outstanding and Awards Excluded from Diluted Earnings Per Share Calculation (Details) - shares shares in Millions	3 Months Ended	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Sep. 29, 2018	Sep. 30, 2017	Oct. 01, 2016
Shares (in millions):
Weighted average number of common and common equivalent shares outstanding (basic)	1,490	1,512	1,499	1,568	1,629
Weighted average dilutive impact of Awards	8	9	8	10	10
Weighted average number of common and common equivalent shares outstanding (diluted)	1,498	1,521	1,507	1,578	1,639
Awards excluded from diluted earnings per share	11	16	12	10	6

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

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- References

No definition available.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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