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Pension and Other Postretirement Benefit Plans - Schedule of Weighted Average Measurement of Assets and Liabilities (Details) | Sep. 27, 2019 | Sep. 28, 2018
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Equity securities | U.S. Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 3.00% | 27.00%
Equity securities | Non-U.S. Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 20.00% | 24.00%
Debt securities | U.S. Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 58.00% | 39.00%
Debt securities | Non-U.S. Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 52.00% | 49.00%
Real estate investments | U.S. Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 0.00% | 0.00%
Real estate investments | Non-U.S. Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 7.00% | 8.00%
Other | U.S. Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 39.00% | 34.00%
Other | Non-U.S. Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 21.00% | 19.00%

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + 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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