Retirement Benefits - Obligations and Funded Status (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Changes in plan assets [Roll Forward]
Employer contributions	$ 3.4
US Plans [Member]
Changes in the benefit obligation [Roll Forward]
Service cost	0	0
Interest cost	11.4	10.6
Non-US Plans [Member]
Changes in the benefit obligation [Roll Forward]
Service cost	3.5	3.6
Interest cost	5.8	4.8
UMWA Plans Postretirement Medical [Member]
Changes in the benefit obligation [Roll Forward]
Service cost	0	0
Interest cost	4.8	5.0
Pension plan [Member]
Changes in the benefit obligation [Roll Forward]
Service cost	3.5	3.6
Interest cost	17.2	15.4
Retirement benefits other than pension [Member]
Changes in the benefit obligation [Roll Forward]
Service cost	0	0.1
Interest cost	$ 5.4	$ 5.5

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- Definition

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

+ References

+ Details

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

+ Details

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the 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 (h)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Service Cost (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6525008

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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