Retirement Benefits - Schedule of Expected Benefit Payments (Details) $ in Millions	Sep. 30, 2021 USD ($)
Pension Benefits
Estimated future benefit payments
2022	$ 327.5
2023	284.4
2024	289.0
2025	288.8
2026	289.9
2027-2031	1,420.8
Other Postretirement Benefits
Estimated future benefit payments
2022	5.8
2023	5.5
2024	5.1
2025	4.8
2026	4.5
2027-2031	$ 17.4

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

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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 fourth 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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