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Pension Benefit Obligations - Target Allocation and Plan Assets Allocations (Details) | Sep. 30, 2023 | Sep. 30, 2022
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United States |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 100.00% |
Percentage of Plan Assets (as a percent) | 100.00% | 100.00%
United States | Equities |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 32.00% |
Percentage of Plan Assets (as a percent) | 33.00% | 36.00%
United States | Debt |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 58.00% |
Percentage of Plan Assets (as a percent) | 56.00% | 48.00%
United States | Cash |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 2.00% |
Percentage of Plan Assets (as a percent) | 2.00% | 5.00%
United States | Property And Other |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 8.00% |
Percentage of Plan Assets (as a percent) | 9.00% | 11.00%
International |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 100.00% |
Percentage of Plan Assets (as a percent) | 100.00% | 100.00%
International | Equities |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 27.00% |
Percentage of Plan Assets (as a percent) | 24.00% | 20.00%
International | Debt |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 61.00% |
Percentage of Plan Assets (as a percent) | 62.00% | 47.00%
International | Cash |  |
Percentage of Plan Assets: |  |
Percentage of Plan Assets (as a percent) | 4.00% | 15.00%
International | Property And Other |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 12.00% |
Percentage of Plan Assets (as a percent) | 10.00% | 18.00%

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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 -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + 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 -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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