Retirement Benefits - Schedule of Expected Benefit Payments (Details) $ in Millions	Sep. 30, 2018 USD ($)
Pension Benefits
Estimated future benefit payments
2019	$ 288.9
2020	268.5
2021	282.1
2022	301.7
2023	278.4
2024 – 2028	1,417.0
Other Postretirement Benefits
Estimated future benefit payments
2019	10.3
2020	6.8
2021	5.5
2022	5.1
2023	4.8
2024 – 2028	$ 19.8

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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-Section 50
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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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

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

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

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