Retirement Benefits - Schedule of Expected Benefit Payments (Details) $ in Millions	Sep. 30, 2023 USD ($)
Pension Benefits
Estimated future benefit payments
2024	$ 302.8
2025	210.5
2026	213.4
2027	226.6
2028	222.4
2029-2033	1,124.7
Other Postretirement Benefits
Estimated future benefit payments
2024	7.3
2025	6.8
2026	6.2
2027	5.6
2028	5.0
2029-2033	$ 15.5

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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

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

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

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

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

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