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Pension Benefit Obligations - Target Allocation and Plan Assets Allocations (Details) | Sep. 30, 2021 | Sep. 30, 2020
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United States |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 100.00% |
Plan assets (as a percent) | 100.00% | 100.00%
United States | Equities |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 40.00% |
Plan assets (as a percent) | 41.00% | 47.00%
United States | Debt. |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 48.00% |
Plan assets (as a percent) | 44.00% | 42.00%
United States | Cash and cash equivalents |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 2.00% |
Plan assets (as a percent) | 5.00% | 1.00%
United States | Property And Other |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 10.00% |
Plan assets (as a percent) | 10.00% | 10.00%
International |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 100.00% |
Plan assets (as a percent) | 100.00% | 100.00%
International | Equities |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 34.00% |
Plan assets (as a percent) | 34.00% | 26.00%
International | Debt. |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 54.00% |
Plan assets (as a percent) | 53.00% | 54.00%
International | Cash and cash equivalents |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 2.00% |
Plan assets (as a percent) | 3.00% | 4.00%
International | Property And Other |  |
Percentage of Plan Assets: |  |
Target allocations (as a percent) | 10.00% |
Plan assets (as a percent) | 10.00% | 16.00%

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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 -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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