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EMPLOYEE BENEFIT PLANS - Weighted Average Assumptions Used for the Pension Calculations (Details)	12 Months Ended
	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%

X

- Definition

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate Of Contribution Increase

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Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Inflation

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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
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-Section 50
-Paragraph 1
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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost 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
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost 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)(3)
-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 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-8

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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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