Retirement Benefit Plans - Estimated Future Payments (Details) $ in Millions	Dec. 31, 2017 USD ($)
U.S. other postretirement benefit plans [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	$ 13.3
2019	12.2
2020	11.7
2021	10.6
2022	9.6
2023-2027	34.2
United States \| Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	22.2
2019	19.5
2020	19.4
2021	19.3
2022	18.5
2023-2027	87.2
Non-US [Member] \| Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2018	20.0
2019	20.5
2020	21.4
2021	22.4
2022	23.6
2023-2027	$ 130.8

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- Definition

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

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.

+ References

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

+ References

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

+ References

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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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