Retirement Plans - Projected Benefit Payments from Plans (Details) $ in Millions	Sep. 30, 2024 USD ($)
Pension Plan
Schedule Of Retirement Plans [Line Items]
2025	$ 269
2026	240
2027	238
2028	231
2029	233
2030 - 2034	1,154
Postretirement Benefits
Schedule Of Retirement Plans [Line Items]
2025	9
2026	9
2027	9
2028	7
2029	6
2030 - 2034	$ 25

Schedule Of Retirement Plans [Line Items]

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- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

+ References

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

+ References

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- Definition

Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

+ References

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

+ References

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- Definition

Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

+ References

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- Details

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