Employee Benefits - Change In Plan Assets (Detail) - Pension Plans, Defined Benefit - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value at beginning of year	$ 1,393.5
Fair Value at end of year	1,506.4	$ 1,393.5
U.S. Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value at beginning of year	1,393.5	1,342.0
Actual Return on Assets	192.5	110.0
Employer Contributions	0.0	0.0
Employee Contributions
Settlement	0.0	0.0
Acquisitions/Divestitures	0.0	0.0
Benefits Paid	(79.6)	(58.5)
Foreign Exchange Rate Changes	0.0	0.0
Fair Value at end of year	1,506.4	1,393.5
Non U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value at beginning of year	139.3	144.3
Actual Return on Assets	12.4	21.9
Employer Contributions	3.0	4.3
Employee Contributions	0.1
Settlement	(6.8)	(7.3)
Acquisitions/Divestitures	18.5	0.0
Benefits Paid	(3.0)	(2.4)
Foreign Exchange Rate Changes	15.2	(21.5)
Fair Value at end of year	$ 178.7	$ 139.3

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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- Definition

Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of increase in plan assets of defined benefit plan from business combination.

+ References

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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.

+ References

No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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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- Definition

Amount of contributions received by defined benefit plan from participant which increases plan assets.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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