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Pension Benefit Obligations - Target Allocation and Plan Assets Allocations (Details)	Sep. 30, 2022	Sep. 30, 2021
United States
Percentage of Plan Assets:
Target allocations (as a percent)	100.00%
Plan assets (as a percent)	100.00%	100.00%
United States | Equity Securities [Member]
Percentage of Plan Assets:
Target allocations (as a percent)	45.00%
Plan assets (as a percent)	36.00%	41.00%
United States | Debt Securities [Member]
Percentage of Plan Assets:
Target allocations (as a percent)	43.00%
Plan assets (as a percent)	48.00%	44.00%
United States | Cash and Cash Equivalents [Member]
Percentage of Plan Assets:
Target allocations (as a percent)	2.00%
Plan assets (as a percent)	5.00%	5.00%
United States | Property And Other
Percentage of Plan Assets:
Target allocations (as a percent)	10.00%
Plan assets (as a percent)	11.00%	10.00%
International.
Percentage of Plan Assets:
Target allocations (as a percent)	100.00%
Plan assets (as a percent)	100.00%	100.00%
International. | Equity Securities [Member]
Percentage of Plan Assets:
Target allocations (as a percent)	35.00%
Plan assets (as a percent)	20.00%	34.00%
International. | Debt Securities [Member]
Percentage of Plan Assets:
Target allocations (as a percent)	56.00%
Plan assets (as a percent)	47.00%	53.00%
International. | Cash and Cash Equivalents [Member]
Percentage of Plan Assets:
Target allocations (as a percent)	2.00%
Plan assets (as a percent)	15.00%	3.00%
International. | Property And Other
Percentage of Plan Assets:
Target allocations (as a percent)	7.00%
Plan assets (as a percent)	18.00%	10.00%

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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=123450688&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=123447040&loc=d3e1928-114920

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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