Employee Retirement Plans - Schedule of Pension Plans (Details) - U.S. - Pension Benefits	Sep. 30, 2025	Sep. 30, 2024
Defined Benefit Plans and Other Postretirement Benefit Plans
Actual	100.00%	100.00%
Target Asset Allocation	100.00%	100.00%
Permitted target allocation range	5.00%
Equity investments
Defined Benefit Plans and Other Postretirement Benefit Plans
Actual	45.60%	52.40%
Target Asset Allocation	46.00%	53.20%
Fixed income funds & cash equivalents
Defined Benefit Plans and Other Postretirement Benefit Plans
Actual	52.30%	44.90%
Target Asset Allocation	51.80%	43.40%
Alternative investments
Defined Benefit Plans and Other Postretirement Benefit Plans
Actual	2.10%	2.70%
Target Asset Allocation	2.20%	3.40%

Defined Benefit Plan, Plan Assets, Target Allocation Range, Percentage

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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

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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

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- Definition

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+ References

No definition available.

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