Retirement Plans - Defined Contribution and Postretirement Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Defined Contribution Retirement Plans
Expense for the defined contribution plans	$ 63	$ 62	$ 60
Deferred Compensation Plans
Total deferred compensation liabilities	203	189
Postretirement Benefit Plans
Change in benefit obligation:
Benefit obligation	$ 18	$ 18

No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Amount of the liabilities for deferred compensation arrangements classified as other.

+ References

No definition available.

+ Details

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- Details

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