Retirement Plans - Weighted Average Allocations (Details)	12 Months Ended
Sep. 27, 2019	Sep. 28, 2018
Non-U.S. Plans
Target asset allocation
Target weighted average asset allocations (as a percent)	100.00%
Weighted average asset allocations
Total weighted average asset allocations (as a percent)	100.00%	100.00%
Non-U.S. Plans \| Equity securities
Target asset allocation
Target weighted average asset allocations (as a percent)	25.00%
Weighted average asset allocations
Total weighted average asset allocations (as a percent)	26.00%	29.00%
Non-U.S. Plans \| Fixed income
Target asset allocation
Target weighted average asset allocations (as a percent)	55.00%
Weighted average asset allocations
Total weighted average asset allocations (as a percent)	53.00%	49.00%
Non-U.S. Plans \| Insurance contracts and other investments
Target asset allocation
Target weighted average asset allocations (as a percent)	17.00%
Weighted average asset allocations
Total weighted average asset allocations (as a percent)	18.00%	20.00%
Non-U.S. Plans \| Real estate investments
Target asset allocation
Target weighted average asset allocations (as a percent)	3.00%
Weighted average asset allocations
Total weighted average asset allocations (as a percent)	3.00%	2.00%
U.S. Plans
Target asset allocation
Target asset allocation funded status minimum (as a percent)	115.00%
Target weighted average asset allocations (as a percent)	100.00%
Weighted average asset allocations
Total weighted average asset allocations (as a percent)	100.00%	100.00%
U.S. Plans \| Equity securities
Target asset allocation
Target weighted average asset allocations (as a percent)	67.00%
Weighted average asset allocations
Total weighted average asset allocations (as a percent)	41.00%	53.00%
U.S. Plans \| Fixed income
Target asset allocation
Target weighted average asset allocations (as a percent)	33.00%
Weighted average asset allocations
Total weighted average asset allocations (as a percent)	59.00%	47.00%
Long-term Target Asset Allocation \| U.S. Plans \| Equity securities
Target asset allocation
Target weighted average asset allocations (as a percent)	5.00%
Long-term Target Asset Allocation \| U.S. Plans \| Fixed income
Target asset allocation
Target weighted average asset allocations (as a percent)	95.00%

Represents the minimum percentage of funded status after which we expect to reach our target asset allocation.

No definition available.

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- References

No definition available.

+ Details

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- References

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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- Definition

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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