Retirement Benefit Plans (Changes in the fair value of plan assets) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Ending balance	$ 424.0	$ 413.0
Retirement Plans [Member]
Beginning balance	407.1
Contributions from plan participants	0	0
Benefits paid	(8.0)	(8.6)
Ending balance	420.6	407.1
Medical Plan [Member]
Beginning balance	10.0
Contributions from plan participants	0.4	0.5
Benefits paid	(2.9)	(1.8)
Ending balance	7.2	10.0
Defined Benefit Plan, Changes in Fair Value of Plan Assets [Member] \| Retirement Plans [Member]
Beginning balance	407.1	338.9
Actual return on plan assets	32.2	51.4
Exchange difference	(26.6)	9.1
Contributions from the company	15.9	15.3
Contributions from plan participants	0	0
Benefits paid	(8.0)	(8.6)
Settlement and other	0	1.0
Ending balance	420.6	407.1
Defined Benefit Plan, Changes in Fair Value of Plan Assets [Member] \| Medical Plan [Member]
Beginning balance	10.0	9.1
Actual return on plan assets	0	1.0
Exchange difference	0.1	0
Contributions from the company	0	0
Contributions from plan participants	0.1	0.2
Benefits paid	(3.0)	(0.3)
Settlement and other	0	0
Ending balance	$ 7.2	$ 10.0

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.

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

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6504226

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Postretirement Benefits

-URI http://asc.fasb.org/extlink&oid=6521376

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Section 50

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-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Benefits

-URI http://asc.fasb.org/extlink&oid=6506267

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

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- Definition

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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- Definition

Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations.

+ References

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-Publisher FASB

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