Retirement and Other Postretirement Benefit Plans - Additional Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
U.S. Non-qualified Defined Benefit Retirement Plans
Amounts recognized on the balance sheet:
Employer contribution to defined benefit retirement plans	$ 0.1		$ 25.7
Expected employer contribution in 2015	4.5
European Defined Benefit Retirement Plans
Amounts recognized on the balance sheet:
Employer contribution to defined benefit retirement plans	1.3	1.4	6.1
Expected employer contribution in next fiscal year	3.9
Postretirement Health Care and Life Insurance Benefit Plans
Amounts recognized on the balance sheet:
Employer contribution to defined benefit retirement plans	0.1	0.1	0.2
Expected employer contribution in next fiscal year	$ 0.6

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

+ 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 (b)(3)

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

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

No definition available.

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ 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 (g)

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

+ Details

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