Retirement Benefits - Schedule of Expected Benefit Payments (Details) $ in Millions	Sep. 30, 2019 USD ($)
Pension Benefits
Estimated future benefit payments
2019	$ 322.2
2020	305.6
2021	322.6
2022	298.5
2023	299.7
2025-2029	1,475.1
Other Postretirement Benefits
Estimated future benefit payments
2019	7.4
2020	6.2
2021	5.9
2022	5.6
2023	5.3
2025-2029	$ 21.0

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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
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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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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