Benefit Plans - Pension Plans with Accumulated Benefit Obligation or Projected Benefit Obligation in Excess of Plan Assets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
U.S. Pension Plans
Pension plans with a projected benefit obligation in excess of plan assets:
Projected benefit obligation	$ 92.5	$ 76.3
Fair value of plan assets	17.5	14.5
Pension plans with an accumulated benefit obligation in excess of plan assets:
Projected benefit obligation	92.5	76.3
Fair value of plan assets	17.5	14.5
Accumulated benefit obligation	85.1	73.1
Non-US Pension Plans
Pension plans with a projected benefit obligation in excess of plan assets:
Projected benefit obligation	460.0	438.2
Fair value of plan assets	258.1	259.0
Pension plans with an accumulated benefit obligation in excess of plan assets:
Projected benefit obligation	453.2	420.4
Fair value of plan assets	252.3	244.5
Accumulated benefit obligation	$ 440.9	$ 411.5

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If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 55

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=34716465&loc=d3e4179-114921

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2417-114920

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

+ Details

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- Definition

If aggregate disclosures are presented, the aggregate projected benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

+ Details

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- Definition

If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2417-114920

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

+ Details

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