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Retirement Benefits (Details 5) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Employer contributions	$ 115.0
Pension Benefits [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year		$ 1,962.3	$ 2,204.4
Actual returns on plan assets and plan expenses		79.7	(41.1)
Employer contributions		125.1	10.3
Participant contributions		0.2	0.3
Effect of currency rates		(17.3)	(4.2)
Benefits paid		(255.4)	(207.4)
Fair value of plan assets at end of year		1,894.6	1,962.3
Other Postretirement Benefits [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year		1.8	2.9
Actual returns on plan assets and plan expenses		(0.8)	(1.0)
Employer contributions		0.0	0.0
Participant contributions		0.0	0.0
Effect of currency rates		0.0	0.0
Benefits paid		(0.3)	(0.1)
Fair value of plan assets at end of year		$ 0.7	$ 1.8

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- Definition

-- None. No documentation exists for this element. --

+ References

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- Definition

The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)
-URI http://asc.fasb.org/extlink&oid=6504192

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of contributions made by the employer to defined benefit plans.

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- Definition

The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets.

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

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The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

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