Retirement Plans - Projected Benefit Payments from Plans (Details) $ in Millions	Sep. 30, 2023 USD ($)
Pension Plan
Schedule Of Retirement Plans [Line Items]
2024	$ 277
2025	235
2026	235
2027	233
2028	172
2029 - 2033	1,160
Postretirement Benefits
Schedule Of Retirement Plans [Line Items]
2024	10
2025	10
2026	9
2027	9
2028	7
2029 - 2033	$ 27

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

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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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