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Pension Benefit Obligations - Target Allocation and Plan Assets (Details) | Sep. 30, 2020 | Sep. 30, 2019
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United States |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 100.00% |
Plan assets (as a percent) | 100.00% | 100.00%
United States | Equities |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 45.00% |
Plan assets (as a percent) | 47.00% | 45.00%
United States | Debt. |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 43.00% |
Plan assets (as a percent) | 42.00% | 44.00%
United States | Cash and cash equivalents |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 2.00% |
Plan assets (as a percent) | 1.00% | 2.00%
United States | Property And Other |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 10.00% |
Plan assets (as a percent) | 10.00% | 9.00%
International |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 100.00% |
Plan assets (as a percent) | 100.00% | 100.00%
International | Equities |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 26.00% |
Plan assets (as a percent) | 26.00% | 36.00%
International | Debt. |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 53.00% |
Plan assets (as a percent) | 54.00% | 31.00%
International | Cash and cash equivalents |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 4.00% |
Plan assets (as a percent) | 4.00% | 3.00%
International | Property And Other |  |
Components of net periodic benefit cost: |  |
Target allocations (as a percent) | 17.00% |
Plan assets (as a percent) | 16.00% | 30.00%

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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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