Retirement and Other Postretirement Benefit Plans - Schedule of Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Postretirement Plans
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Net loss (gain)		$ (0.9)
Amortization of actuarial (losses) gains	$ 1.1	0.7
Total recognized in other comprehensive income (pre-tax)	1.1	(0.2)
U.S. Plans \| Defined Benefit Retirement Plans
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Net loss (gain)	0.1	0.1
Amortization of actuarial (losses) gains	(0.8)	(0.3)
Total recognized in other comprehensive income (pre-tax)	(0.7)	(0.2)
European Plans \| Defined Benefit Retirement Plans
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income
Net loss (gain)	2.3	(5.0)
Amortization of actuarial (losses) gains	(0.4)	(0.7)
Effect of foreign exchange	2.5	(4.0)
Total recognized in other comprehensive income (pre-tax)	$ 4.4	$ (9.7)

Defined benefit plan amounts recognized in other comprehensive income amortization of actuarial gain losses before tax.

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- Definition

Represents the effect of change in the exchange rate before tax recognized in other comprehensive income, including amounts arising during the period and reclassification adjustments of other comprehensive income as a result of being recognized as components of net periodic benefit cost for the period.

+ References

No definition available.

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- Definition

Amount, before tax, after reclassification adjustment, of increase (decrease) in accumulated other comprehensive income from gain (loss) of defined benefit plan.

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

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- Definition

Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

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