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EMPLOYEE BENEFIT PLANS - Weighted Average Assumptions Used for the Pension Calculations (Details) | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
United States |  |  |
Weighted average assumptions used for the pension calculations |  |  |
Discount rate for net periodic benefit costs | 4.84% | 5.77% | 5.44%
Discount rate for year-end obligations | 5.21% | 4.84% | 5.77%
Expected return on plan assets | 4.40% | 4.40% | 4.50%
UK Plans |  |  |
Weighted average assumptions used for the pension calculations |  |  |
Discount rate for year-end obligations | 5.80% |  |
Contribution increase rate | 3.00% |  |
Inflation rate | 3.00% |  |
Germany Plans |  |  |
Weighted average assumptions used for the pension calculations |  |  |
Discount rate for year-end obligations | 4.00% |  |
Contribution increase rate | 2.50% |  |
Participant salaries increase rate | 4.00% |  |
Inflation rate | 3.00% |  |

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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (j)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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