Lease and Other Commitments and Contingencies (Details) $ in Millions	12 Months Ended
Sep. 28, 2019 USD ($) Employee	Sep. 29, 2018 USD ($)	Sep. 30, 2017 USD ($)
Lease and Other Commitments and Contingencies [Abstract]
New capital lease obligations	$ 0	$ 31	$ 5
Minimum lease payments or contingent rentals	31	29
Asset retirement obligations	10	10
Rent expense from operating leases	83	$ 72	$ 67
Future Minimum Lease Payments for Capital Leases [Abstract]
2020	38
2021	29
2022	25
2023	14
2024	9
Thereafter	11
Total net minimum payments	126
Less: amount representing interest	(9)
Present value of net minimum lease payments	117
Future Minimum Lease Payments for Operating Leases [Abstract]
2020	108
2021	96
2022	78
2023	59
2024	44
Thereafter	169
Total net minimum payments	554
Sale-Leaseback Transactions [Abstract]
Deferred gain on sale-leaseback transactions	$ 19
Collective Bargaining Agreements [Abstract]
Number of employees \| Employee	48,000
Percentage of employees covered by collective bargaining agreements	20.00%
Period of time with no significant work stoppages or other labor disputes with employees under collective bargaining agreements	3 years

No definition available.

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- Definition

The percentage of employees covered by collective bargaining agreements.

+ References

No definition available.

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Period of time with no significant work stoppages or other labor disputes with employees under collective bargaining agreements, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Number of persons employed by the Entity

+ References

No definition available.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of increase in lease obligation from new lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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- Definition

Amount due based upon the occurrence of an event specified in the contractual terms.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737

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- References

No definition available.

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- Definition

Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References