Amount of contributions to defined contribution schemes.

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- Definition

Annual cash contribution.

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No definition available.

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- Definition

Definite benefit plan employee retirement age.

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- Definition

Definite benefit plan expected change in discount rate.

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No definition available.

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- Definition

Definite benefit plan expected change project benefit obligation due to discount rate change.

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No definition available.

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- Definition

Definite benefit plan expected change project benefit obligation due to inflation rate change.

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No definition available.

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- Definition

Definite benefit plan expected net pension cost due change in discount rate.

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- Definition

Definite benefit plan expected net pension cost due change in inflation rate.

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- Definition

Maximum Percent of investment in individual securities.

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No definition available.

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- Definition

Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

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- Definition

Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

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Amount, after tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Pension and Post-employment Benefits - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Retirement age of service		65 years
Annual cash contribution		$ 1.0
Percentage change in discount rate		0.25%
Amount change in PBO due to discount rate		$ 25.0
Amount change in net pension credit due to discount rate		0.1
Amount change in PBO due to change price inflation		$ 18.0
Percentage change in price inflation		0.25%
Amount change in net pension credit due price inflation		$ 1.5
Maximum percentage of Plan's assets invested in individual company's investment funds		5.00%
Accumulated benefit obligation for the Plan		$ 721.4	$ 710.2
Amount of contributions to defined contribution schemes		7.9	7.9
Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Net pension credit, total	$ 5.2
Forecast [Member] \| Selling, General and Administrative Expenses [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost, total	$ 1.2
Europe [Member] \| Foreign Pension Plan [Member] \| Performance Chemicals [Member]
Defined Benefit Plan Disclosure [Line Items]
Post-employment obligations European businesses		$ 4.7	$ 4.1
United Kingdom Government Gilts [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of asset allocation, actual		10.00%	18.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation		85.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation		15.00%
German Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost, total		$ 0.2	$ 0.2	$ 0.2
Net pension credit, total		0.8	$ 0.6	$ 0.7
Amount of unrecognized actuarial net losses, net of tax		2.6
Amount tax on unrecognized actuarial net losses		$ 0.8
United Kingdom Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of asset allocation, actual		100.00%	100.00%	100.00%
United Kingdom Plan [Member] \| Index-Tracking Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of asset allocation, actual		30.00%	37.00%
United Kingdom Plan [Member] \| Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of asset allocation, actual		53.00%	66.00%	62.00%
United Kingdom Plan [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of asset allocation, actual		38.00%	25.00%	34.00%