XBRL Financials

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2018	Apr. 30, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q1
Trading Symbol	IOSP
Entity Registrant Name	INNOSPEC INC.
Entity Central Index Key	0001054905
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		24,402,972

Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Net sales	$ 360.7	$ 294.3
Cost of goods sold	(256.2)	(203.4)
Gross profit	104.5	90.9
Operating expenses:
Selling, general and administrative	(67.3)	(56.4)
Research and development	(8.3)	(7.4)
Foreign exchange loss on liquidation of subsidiary	0.0	(1.8)
Total operating expenses	(75.6)	(65.6)
Operating income	28.9	25.3
Other income, net	2.5	0.1
Interest expense, net	(1.7)	(2.2)
Income before income taxes	29.7	23.2
Income taxes	(7.5)	(6.0)
Net income	$ 22.2	$ 17.2
Earnings per share:
Basic	$ 0.91	$ 0.71
Diluted	$ 0.90	$ 0.70
Weighted average shares outstanding (in thousands):
Basic	24,369	24,087
Diluted	24,574	24,527

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 22.2	$ 17.2
Changes in cumulative translation adjustment, net of tax of $(0.1) million and $(0.1) million respectively	6.4	3.5
Changes in unrealized gains on derivative instruments, net of tax of $(0.2) million and $(0.1) million respectively	0.9	0.2
Amortization of prior service credit, net of tax of $0.1 million and $0.1 million respectively	(0.2)	(0.2)
Amortization of actuarial net losses, net of tax of $(0.1) million and $(0.2) million respectively	0.4	1.0
Total other comprehensive income	7.5	4.5
Total comprehensive income	$ 29.7	$ 21.7

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Changes in cumulative translation adjustment, tax	$ (0.1)	$ (0.1)
Unrealized gains on derivative instruments, tax	(0.2)	(0.1)
Amortization of prior service credit, tax	0.1	0.1
Amortization of actuarial net losses, tax	$ (0.1)	$ (0.2)

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 78.1	$ 90.2
Trade and other accounts receivable (less allowances of $5.3 million and $4.1 million respectively)	280.3	244.5
Inventories (less allowances of $10.5 million and $12.6 million respectively):
Finished goods	182.1	145.9
Raw materials	65.6	63.9
Total inventories	247.7	209.8
Prepaid expenses	13.2	13.1
Prepaid income taxes	2.8	2.8
Other current assets	0.6	1.1
Total current assets	622.7	561.5
Property, plant and equipment:
Gross cost	321.4	327.2
Less accumulated depreciation	(124.6)	(131.2)
Net property, plant and equipment	196.8	196.0
Goodwill	364.1	361.8
Other intangible assets	158.3	163.3
Deferred tax assets	6.4	6.5
Pension asset	117.8	116.0
Other non-current assets	6.8	5.1
Total assets	1,472.9	1,410.2
Current liabilities:
Accounts payable	128.2	117.9
Accrued liabilities	130.6	104.1
Current portion of long-term debt	15.8	15.8
Current portion of finance leases	2.5	2.7
Current portion of plant closure provisions	4.2	5.2
Current portion of accrued income taxes	11.3	15.8
Total current liabilities	292.6	261.5
Long-term debt, net of current portion	197.8	202.6
Finance leases, net of current portion	2.7	3.2
Plant closure provisions, net of current portion	42.7	40.9
Accrued income taxes, net of current portion	43.6	41.7
Unrecognized tax benefits, net of current portion	3.1	2.5
Deferred tax liabilities	46.7	45.0
Pension liabilities and post-employment benefits	17.0	16.5
Other non-current liabilities	1.9	2.0
Total liabilities	648.1	615.9
Equity:
Common stock, $0.01 par value, authorized 40,000,000 shares, issued 29,554,500 shares	0.3	0.3
Additional paid-in capital	321.1	320.4
Treasury stock (5,151,528 and 5,204,181 shares at cost, respectively)	(93.2)	(93.3)
Retained earnings	627.2	605.0
Accumulated other comprehensive loss	(31.0)	(38.5)
Total Innospec stockholders' equity	824.4	793.9
Non-controlling interest	0.4	0.4
Total equity	824.8	794.3
Total liabilities and equity	$ 1,472.9	$ 1,410.2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Allowances for doubtful accounts	$ 5.3	$ 4.1
Inventory allowances	$ 10.5	$ 12.6
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	29,554,500	29,554,500
Treasury stock, shares	5,151,528	5,204,181

Condensed Consolidated Statements of Cash Flows - USD ($)
$ in Millions

3 Months Ended

Mar. 31, 2018

Mar. 31, 2017

Cash Flows from Operating Activities

Net income

$ 22.2

$ 17.2

Adjustments to reconcile net income to net cash provided by operating activities:

Depreciation and amortization

^[1]

12.6

12.3

Deferred taxes

1.7

1.0

Foreign exchange loss on liquidation of subsidiary

0.0

1.8

Cash contributions to defined benefit pension plans

(0.3)

(0.2)

Non-cash movements on defined benefit pension plans

(1.1)

(0.9)

Stock option compensation

0.8

1.0

Changes in assets and liabilities, net of effects of acquired and divested companies:

Trade and other accounts receivable

(33.6)

(64.2)

Inventories

(37.1)

(22.8)

Prepaid expenses

(0.1)

(1.0)

Accounts payable and accrued liabilities

34.6

31.4

Accrued income taxes

(2.8)

3.9

Plant closure provisions

0.7

1.1

Unrecognized tax benefits

0.6

0.0

Other assets and liabilities

(0.2)

(0.5)

Net cash used in operating activities

(2.0)

(19.9)

Cash Flows from Investing Activities

Capital expenditures

(3.8)

(6.7)

Internally developed software

(0.8)

0.0

Net cash used in investing activities

(4.6)

(6.7)

Cash Flows from Financing Activities

Repayments of revolving credit facility

(5.0)

(30.0)

Repayments of finance leases

(0.7)

(0.6)

Issue of treasury stock

1.0

Repurchase of common stock

(1.1)

(0.9)

Net cash used in financing activities

(5.8)

(30.5)

Effect of foreign currency exchange rate changes on cash

0.3

0.6

Net change in cash and cash equivalents

(12.1)

(56.5)

Cash and cash equivalents at beginning of period

90.2

101.9

Cash and cash equivalents at end of period

$ 78.1

$ 45.4

[1]	Amortization of deferred finance costs of $0.1 million (2017 - $0.2 million) are included in depreciation and amortization in the condensed consolidated statement of cash flow but in interest expense in the condensed consolidated statement of income.

Condensed Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Cash Flows [Abstract]
Amortization of deferred finance costs	$ 0.1	$ 0.2

Condensed Consolidated Statements of Equity - 3 months ended Mar. 31, 2018 - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Non-Controlling Interest [Member]
Beginning Balance at Dec. 31, 2017	$ 794.3	$ 0.3	$ 320.4	$ (93.3)	$ 605.0	$ (38.5)	$ 0.4
Net income	22.2				22.2
Changes in cumulative translation adjustment, net of tax	6.4					6.4
Changes in unrealized gains on derivative instruments, net of tax	0.9					0.9
Treasury stock reissued	1.1		(0.1)	1.2
Treasury stock repurchased	(1.1)			(1.1)
Stock option compensation	0.8		0.8
Amortization of prior service credit, net of tax	(0.2)					(0.2)
Amortization of actuarial net losses, net of tax	0.4					0.4
Ending Balance at Mar. 31, 2018	$ 824.8	$ 0.3	$ 321.1	$ (93.2)	$ 627.2	$ (31.0)	$ 0.4

Basis of Presentation	3 Months Ended
Basis of Presentation	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	*NOTE 1 – BASIS OF PRESENTATION* The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X under the Securities Exchange Act of 1934. Accordingly, they do not include all the information and notes necessary for a comprehensive presentation of financial position, results of operations and cash flows. It is our opinion, however, that all adjustments (consisting of normal, recurring adjustments, unless otherwise disclosed) have been made which are necessary for the condensed consolidated financial statements to be fairly stated. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017 filed on February 15, 2018. The results for the interim period covered by this report are not necessarily indicative of the results to be expected for the full year. We have reclassified certain prior period amounts to conform to the current period presentation. See Note 15 of the Notes to the Condensed Consolidated Financial Statements for additional information. When we use the terms “Innospec,” “the Corporation,” “the Company,” “Registrant,” “we,” “us” and “our,” we are referring to Innospec Inc. and its consolidated subsidiaries unless otherwise indicated or the context otherwise requires.

Segement Reporting

3 Months Ended

Mar. 31, 2018

Segment Reporting [Abstract]

Segement Reporting

NOTE 2 – SEGMENT REPORTING

The Company reports its financial performance based on the four reportable segments Fuel Specialties, Performance Chemicals, Oilfield Services and Octane Additives.

The Fuel Specialties, Performance Chemicals and Oilfield Services segments operate in markets where we actively seek growth opportunities although their ultimate customers are different. The Octane Additives segment is expected to decline in the near future as our one remaining refinery customer transitions to unleaded fuel.

The Company evaluates the performance of its segments based on operating income. The following tables analyze sales and other financial information by the Company’s reportable segments:


	Three Months Ended March 31
(in millions)	2018			2017
Net Sales:
Refinery and Performance	$	111.0		$	100.4
Other		32.4			26.0

Fuel Specialties		143.4			126.4

Personal Care		57.8			47.5
Home Care		34.2			26.9
Other		32.0			20.1

Performance Chemicals		124.0			94.5

Oilfield Services		92.9			66.5
Octane Additives		0.4			6.9

	$	360.7		$	294.3


	Three Months Ended March 31
(in millions)	2018			2017
Net sales:
Fuel Specialties	$	143.4		$	126.4
Performance Chemicals		124.0			94.5
Oilfield Services		92.9			66.5
Octane Additives		0.4			6.9

	$	360.7		$	294.3

Gross profit/(loss):
Fuel Specialties	$	48.5		$	46.1
Performance Chemicals		25.4			16.7
Oilfield Services		31.4			25.4
Octane Additives		(0.8	)		2.7

	$	104.5		$	90.9


Operating income/(loss):
Fuel Specialties	$	28.2		$	27.0
Performance Chemicals		12.1			6.0
Oilfield Services		3.0			3.0
Octane Additives		(1.4	)		2.0
Corporate costs		(13.0	)		(10.9	)
Foreign exchange loss on liquidation of subsidiary		0.0			(1.8	)

Total operating income	$	28.9		$	25.3

The following table presents a summary of the depreciation and amortization charges incurred by the Company’s reportable segments:


	Three Months Ended March 31
(in millions)	2018		2017
Depreciation:
Fuel Specialties	$	1.0	$	1.0
Performance Chemicals		2.7		2.2
Oilfield Services		1.5		1.6
Octane Additives		0.3		0.2
Corporate		0.3		0.2

	$	5.8	$	5.2

Amortization:
Fuel Specialties	$	0.0	$	0.2
Performance Chemicals		2.3		1.9
Oilfield Services		2.6		3.0
Corporate		1.8		1.8

	$	6.7	$	6.9

Earnings per Share

3 Months Ended

Mar. 31, 2018

Earnings Per Share [Abstract]

Earnings per Share

NOTE 3 – EARNINGS PER SHARE

Basic earnings per share is based on the weighted average number of common shares outstanding during the period. Diluted earnings per share includes the effect of options that are dilutive and outstanding during the period. Per share amounts are computed as follows:


	Three Months Ended March 31
	2018		2017
Numerator (in millions):
Net income available to common stockholders	$	22.2	$	17.2

Denominator (in thousands):
Weighted average common shares outstanding		24,369		24,087
Dilutive effect of stock options and awards		205		440

Denominator for diluted earnings per share		24,574		24,527

Net income per share, basic:	$	0.91	$	0.71

Net income per share, diluted:	$	0.90	$	0.70

In the three months ended March 31, 2018, the average number of anti-dilutive options excluded from the calculation of diluted earnings per share were 18,468 (three months ended March 31, 2017 – 9,422).

Goodwill

3 Months Ended

Mar. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill

NOTE 4 – GOODWILL

The following table summarizes goodwill at the balance sheet dates:


(in millions)	Total
At December 31, 2017
Gross cost ⁽¹⁾	$	598.3
Accumulated impairment losses		(236.5	)

Net book amount	$	361.8

Exchange effect		2.3
At March 31, 2018
Gross cost ⁽¹⁾	$	600.6
Accumulated impairment losses		(236.5	)

Net book amount	$	364.1

⁽¹⁾	Gross cost for 2018 and 2017 is net of $298.5 million of historical accumulated amortization.

Other Intangible Assets

3 Months Ended

Mar. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Other Intangible Assets

NOTE 5 – OTHER INTANGIBLE ASSETS

The following table summarizes the other intangible assets movement year on year:


	Three Months Ended March 31
(in millions)	2018			2017
Gross cost at January 1	$	295.8		$	248.6
Acquisitions		0.0			33.5
Internally developed software		0.8			0.0
Exchange effect		1.2			0.1

Gross cost at March 31		297.8			282.2

Accumulated amortization at January 1		(132.5	)		(104.2	)
Amortization expense		(6.7	)		(6.9	)
Exchange effect		(0.3	)		0.1

Accumulated amortization at March 31		(139.5	)		(111.0	)

Net book amount at March 31	$	158.3		$	171.2

Internally developed software has been capitalized in relation to the information system platform for our Performance Chemicals European businesses.

Amortization expense


	Three Months Ended March 31
(in millions)	2018			2017
Product rights	$	(0.9	)	$	(0.9	)
Brand names		(0.3	)		(0.3	)
Technology		(0.9	)		(0.9	)
Customer relationships		(2.6	)		(2.6	)
Non-compete agreements		0.0			(0.2	)
Marketing related		0.0			(0.2	)
Internally developed software		(2.0	)		(1.8	)

Total	$	(6.7	)	$	(6.9	)

Pension and Post Employment Benefits

3 Months Ended

Mar. 31, 2018

Retirement Benefits [Abstract]

Pension and Post Employment Benefits

NOTE 6 – PENSION AND POST EMPLOYMENT BENEFITS

The Company maintains a defined benefit pension plan (the “Plan”) covering a number of its current and former employees in the United Kingdom, although it does also have other much smaller pension arrangements in the U.S. and overseas. The Plan is closed to future service accrual but has a large number of deferred and current pensioners.

The net service cost for the three months ended March 31, 2018 is $0.3 million (three months ended March 31, 2017 – $0.2 million) has been recognized in selling, general and administrative expenses within corporate costs. The following table shows the income statement effect recognized within other income, net:


	Three Months Ended March 31
(in millions)	2018			2017
Plan net pension credit/(charge):
Interest cost on projected benefit obligation		(3.9	)		(3.7	)
Expected return on plan assets		5.7			5.9
Amortization of prior service credit		0.3			0.3
Amortization of actuarial net losses		(0.5	)		(1.2	)

	$	1.6		$	1.3

The amortization of prior service credit and actuarial net losses is a reclassification out of accumulated other comprehensive loss into other income and expense.

The Company also maintains an unfunded defined benefit pension plan covering a number of its current and former employees in Germany (the “German plan”) within our Fuel Specialties segment. The German plan is closed to new entrants and has no assets. The net service cost for the German plan for the three months ended March 31, 2018 was $0.0 million (three months ended March 31, 2017 – $0.0 million). The following table shows the income statement effect recognized within other income and expense:


	Three Months Ended March 31
(in millions)	2018			2017
Plan net pension credit/(charge):
Interest cost on projected benefit obligation		(0.1	)		(0.1	)
Amortization of actuarial net losses		(0.1	)		(0.1	)

	$	(0.2	)	$	(0.2	)

As at March 31, 2018, our Performance Chemicals segment has post-employment obligations in its European businesses with a liability of $4.8 million (December 31, 2017 – $4.7 million).

Income Taxes

3 Months Ended

Mar. 31, 2018

Income Tax Disclosure [Abstract]

Income Taxes

NOTE 7 – INCOME TAXES

A roll-forward of unrecognized tax benefits is as follows:


(in millions)	March 31, 2018		December 31, 2017
Opening balance at January 1	$	2.2	$	2.2
Additions for tax positions of prior periods		0.4		0.5
Reductions due to lapsed statute of limitations		0.0		(0.5	)

Closing balance	$	2.6	$	2.2

We recognize accrued interest and penalties associated with unrecognized tax benefits as part of income taxes in our condensed consolidated statements of income. Related to the unrecognized tax benefits noted above, we have accrued a net increase in interest and penalties of $0.2 million during 2018 and a net increase in interest and penalties of $0.2 million in 2017. Total accrued interest and penalties at March 31, 2018 on all remaining unrecognized tax benefits amounted to $0.5 million (December 31, 2017 - $0.3 million).

All of the $3.1 million of unrecognized tax benefits, interest and penalties, would impact our effective tax rate if recognized.

The Company or one of its subsidiaries files income tax returns with the U.S. federal government, and various state and foreign jurisdictions. As previously disclosed, the Company and its U.S. subsidiaries were subject to a federal income tax examination in respect of 2015. The examination was completed in the first quarter of 2018 at no additional cost to the Company.

As previously disclosed, tax audits have been opened by the Italian tax authorities in respect of Innospec Performance Chemicals Italia Srl, acquired as part of the Huntsman business in respect of the period 2011 to 2013 inclusive. In the fourth quarter of 2017, the Company recorded an unrecognized tax benefit of $0.5 million, together with associated interest of $0.2 million in relation to the 2011 tax audit. As a consequence of information received in the first quarter of 2018, the Company believes that additional tax of $0.4 million, together with associated interest of $0.1 million, may arise as a result of the 2012 audit. There is insufficient evidence to conclude on the position in relation to 2013 at the current time. As any additional tax arising as a consequence of the tax audit would be reimbursed by the previous owner under the terms of the sale and purchase agreement, the Company has recorded an unrecognized tax benefit inclusive of interest of $0.5 million in the quarter, together with an indemnification asset of the same amount to reflect the fact that the final liability would be reimbursed by the previous owner.

The Company and its U.S. subsidiaries remain open to examination by the IRS for years 2014 onwards under the statute of limitations. The Company’s subsidiaries in foreign tax jurisdictions are open to examination including France (2014 onwards), Germany (2015 onwards), Switzerland (2015 onwards) and the United Kingdom (2016 onwards).

Long-Term Debt

3 Months Ended

Mar. 31, 2018

Debt Disclosure [Abstract]

Long-Term Debt

NOTE 8 – LONG-TERM DEBT

Long-term debt consists of the following:


(in millions)	March 31, 2018			December 31, 2017
Revolving credit facility	$	116.0		$	121.0
Term loan		99.0			99.0
Deferred finance costs		(1.4	)		(1.6	)

	$	213.6		$	218.4
Due within one year		(15.8	)		(15.8	)

Due after one year	$	197.8		$	202.6

Plant Closure Provisions

3 Months Ended

Mar. 31, 2018

Restructuring and Related Activities [Abstract]

Plant Closure Provisions

NOTE 9 – PLANT CLOSURE PROVISIONS

The liability for estimated closure costs of Innospec’s manufacturing facilities includes costs for decontamination and environmental remediation activities (“remediation”). The principal site giving rise to remediation liabilities is the manufacturing site at Ellesmere Port in the United Kingdom. There are also remediation liabilities on a smaller scale in respect of our other manufacturing sites in the U.S. and the rest of Europe.

Movements in the provisions are summarized as follows:


	Three Months Ended March 31
(in millions)	2018			2017
Total at January 1	$	46.1		$	39.5
Charge for the period		1.6			1.5
Utilized in the period		(0.9	)		(0.4	)
Exchange effect		0.1			0.0

Total at March 31		46.9			40.6
Due within one year		(4.2	)		(6.4	)

Due after one year	$	42.7		$	34.2

Amounts due within one year refer to provisions where expenditure is expected to arise within one year of the balance sheet date.

Fair Value Measurements

3 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements

NOTE 10 – FAIR VALUE MEASUREMENTS

The following table presents the carrying amount and fair values of the Company’s financial assets and liabilities measured on a recurring basis:


	March 31, 2018				December 31, 2017
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Assets
Non-derivatives:
Cash and cash equivalents	$	78.1	$	78.1	$	90.2	$	90.2
Derivatives (Level 1 measurement):
Other current and non-current assets:
Foreign currency forward exchange contracts		0.6		0.6		1.1		1.1
Interest rate swaps		2.6		2.6		1.5		1.5

Liabilities
Non-derivatives:
Long-term debt (including current portion)	$	213.6	$	213.6	$	218.4	$	218.4
Finance leases (including current portion)		5.2		5.2		5.9		5.9
Non-financial liabilities (Level 3 measurement):
Stock equivalent units		12.5		12.5		13.6		13.6

The following methods and assumptions were used to estimate the fair values of financial instruments:

Cash and cash equivalents: The carrying amount approximates fair value because of the short-term maturities of such instruments.

Derivatives: The fair value of derivatives relating to foreign currency forward exchange contracts and interest rate swaps are derived from current settlement prices and comparable contracts using current assumptions. Foreign currency forward exchange contracts primarily relate to contracts entered into to hedge future known transactions or hedge balance sheet net cash positions. The movements in the carrying amounts and fair values of these contracts are largely due to changes in exchange rates against the U.S. dollar. Interest rate swaps relate to contracts taken out to hedge interest rate risk on a portion of our credit facilities borrowing.

Long-term debt and finance leases: Long-term debt principally comprises the term loan and revolving credit facility, which are shown net of deferred finance costs that have been capitalized. The fair value of long-term debt approximates to the carrying value, as the discounting to its present value is offset by the interest rate swaps. Finance leases relate to certain fixed assets in our Fuel Specialties and Oilfield Services segments. The carrying amount of long-term debt and finance leases approximates to the fair value.

Stock equivalent units: The fair values of stock equivalent units are calculated at each balance sheet date using either the Black-Scholes or Monte Carlo method depending on the terms of each grant.

Derivative Instruments and Risk Management	3 Months Ended
Derivative Instruments and Risk Management	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Risk Management	*NOTE 11 – DERIVATIVE INSTRUMENTS AND RISK MANAGEMENT* The Company enters into various foreign currency forward exchange contracts to minimize currency exchange rate exposure from expected future cash flows. As at March 31, 2018 the contracts have maturity dates of up to twelve months at the date of inception. These foreign currency forward exchange contracts have not been designated as hedging instruments, and their impact on the income statement for the first three months of 2018 was a loss of $0.5 million (first three months of 2017: loss of $0.5 million). The Company enters into interest rate swaps to minimize interest rate exposure related to a part of our borrowing requirements. These interest rate swaps have been designated as hedging instruments, and their impact on accumulated other comprehensive loss for the first three months of 2018 was a gain of $1.1 million (first three months of 2017: gain of $0.3 million).

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	*NOTE 12 – COMMITMENTS AND CONTINGENCIES* Legal matters While we are involved from time to time in claims and legal proceedings that result from, and are incidental to, the conduct of our business including business and commercial litigation, employee and product liability claims, there are no material pending legal proceedings to which the Company or any of its subsidiaries is a party, or of which any of their property is subject. It is possible, however, that an adverse resolution of an unexpectedly large number of such individual claims or proceedings could in the aggregate have a material adverse effect on the results of operations for a particular year or quarter. Guarantees The Company and certain of the Company’s consolidated subsidiaries are contingently liable for certain obligations of affiliated companies primarily in the form of guarantees of debt and performance under contracts entered into as a normal business practice. This includes guarantees of non-U.S. excise taxes and customs duties. As at March 31, 2018, such guarantees which are not recognized as liabilities in the condensed consolidated financial statements amounted to $5.2 million. Under the terms of the guarantee arrangements, generally the Company would be required to perform should the affiliated company fail to fulfil its obligations under the arrangements. In some cases, the guarantee arrangements have recourse provisions that would enable the Company to recover any payments made under the terms of the guarantees from securities held of the guaranteed parties’ assets. The Company and its affiliates have numerous long-term sales and purchase commitments in their various business activities, which are expected to be fulfilled with no adverse consequences material to the Company.

Stock-Based Compensation Plans

3 Months Ended

Mar. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation Plans

NOTE 13 – STOCK-BASED COMPENSATION PLANS

The Company grants stock options and stock equivalent units (“SEUs”) from time to time as a long-term performance incentive. In certain cases the grants are subject to performance conditions such as the Company’s stock price. Where performance conditions apply the Monte Carlo simulation model is used to determine the fair values. Otherwise the Black-Scholes model is used to determine the fair values.

Stock option plans

The following table summarizes the transactions of the Company’s stock option plans for the three months ended March 31, 2018:


	Number of Options			Weighted Average Exercise Price		Weighted Average Grant-Date Fair Value
Outstanding at December 31, 2017		357,666		$	13.74	$	35.69
Granted - at discount		71,227		$	0.00	$	57.53
- at market value		18,850		$	68.20	$	16.23
Exercised		(69,569	)	$	13.83	$	26.40
Forfeited		(11,874	)	$	19.69	$	27.17

Outstanding at March 31, 2018		366,300		$	13.66	$	40.97

At March 31, 2018, there were 49,272 stock options that were exercisable, of which 2,672 had performance conditions attached.

The stock option compensation cost for the first three months of 2018 was $0.8 million (first three months of 2017 – $1.0 million). The total intrinsic value of options exercised in the first three months of 2018 was $1.9 million (first three months of 2017 – $1.8 million).

The total compensation cost related to non-vested stock options not yet recognized at March 31, 2018 was $8.9 million and this cost is expected to be recognized over the weighted-average period of 2.28 years.

Stock equivalent units

The following table summarizes the transactions of the Company’s SEUs for the three months ended March 31, 2018:


	Number of SEUs			Weighted Average Exercise Price		Weighted Average Grant-Date Fair Value
Outstanding at December 31, 2017		400,342		$	3.10	$	46.65
Granted - at discount		101,278		$	0.00	$	57.44
- at market value		5,658		$	68.20	$	16.23
Exercised		(48,852	)	$	3.57	$	28.12
Forfeited		(16,554	)	$	1.40	$	37.14

Outstanding at March 31, 2018		441,872		$	3.23	$	51.14

At March 31, 2018 there were 51,863 SEUs that are exercisable, of which 43,834 had performance conditions attached.

The charges for SEUs are spread over the life of the award subject to a revaluation to fair value each quarter. The revaluation may result in a charge or a credit to the income statement in the quarter dependent upon our share price and other performance criteria.

The SEU compensation cost for the first three months of 2018 was $1.2 million (first three months of 2017 – $0.9 million). The total intrinsic value of SEUs exercised in the first three months of 2018 was $1.6 million (first three months of 2017 - $0.9 million).

The weighted-average remaining vesting period of non-vested SEUs is 2.12 years.

Reclassifications out of Accumulated Other Comprehensive Loss

3 Months Ended

Mar. 31, 2018

Equity [Abstract]

Reclassifications out of Accumulated Other Comprehensive Loss

NOTE 14 – RECLASSIFICATIONS OUT OF ACCUMULATED OTHER COMPREHENSIVE LOSS

Reclassifications out of accumulated other comprehensive loss for the first three months of 2018 were:


(in millions) Details about AOCL Components	Amount Reclassified from AOCL			Affected Line Item in the Statement where Net Income is Presented
Defined benefit pension plan items:
Amortization of prior service credit	$	(0.3	)		See ⁽¹⁾ below
Amortization of actuarial net losses		0.5			See⁽¹⁾ below

		0.2			Total before tax
		0.0			Income tax expense

Total reclassifications	$	0.2			Net of tax

⁽¹⁾	These items are included in other income and expense. See Note 6 of the Notes to the Condensed Consolidated Financial Statements for additional information.

Changes in accumulated other comprehensive loss for the first three months of 2018, net of tax, were:


(in millions)	Derivative instruments		Defined Benefit Pension Plan Items			Cumulative Translation Adjustments			Total
Balance at December 31, 2017	$	1.2	$	(3.2	)	$	(36.5	)	$	(38.5	)

Other comprehensive income before reclassifications		0.9		0.0			6.4			7.3
Amounts reclassified from AOCL		0.0		0.2			0.0			0.2

Total other comprehensive income		0.9		0.2			6.4			7.5

Balance at March 31, 2018	$	2.1	$	(3.0	)	$	(30.1	)	$	(31.0	)

Recently Issued Accounting Pronouncements	3 Months Ended
Recently Issued Accounting Pronouncements	Mar. 31, 2018
Accounting Changes and Error Corrections [Abstract]
Recently Issued Accounting Pronouncements	*NOTE 15 – RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS* In the first quarter of 2018 we have applied ASU 2017-07, Compensation-Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. ASU 2017-07 requires companies to present the service cost component of net benefit cost in the same line items in which they report compensation cost. Companies will present all other components of net benefit cost outside operating income, if this subtotal is presented. The new standard is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years. We have adopted the new standard on January 1, 2018 resulting in a restatement of the prior period comparatives with a reduction to operating income of $1.1 million and a corresponding increase in other non-operating income. In May 2014, the FASB issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers (Topic 606). ASU 2014-09 is based on principles that govern the recognition of revenue at an amount an entity expects to be entitled when products are transferred to customers. The new standard is effective for annual reporting periods beginning after December 15, 2017. We have adopted the new revenue standard on January 1, 2018 utilizing the modified retrospective approach. Adoption of the new standard has not had a material impact on our financial statements. In February 2016, the FASB issued Accounting Standards Update (ASU) 2016-02, Revision to Lease Accounting, which amends ASC Topic 842, Leases. The ASU requires lessees to recognize a right-of-use asset and a lease liability for virtually all of their leases (other than leases that meet the definition of a short-term lease). The new standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. The new standard must be adopted using a modified retrospective transition method, and provides for certain practical expedients. Transition will require application of the new guidance at the beginning of the earliest comparative period presented. We are currently evaluating the new standard to determine how it will affect our financial reporting. At this time we expect the principal effect of adopting the new standard will be to report the value of assets and obligations for current operating leases.

Related Party Transactions	3 Months Ended
Related Party Transactions	Mar. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	*NOTE 16 – RELATED PARTY TRANSACTIONS* Mr. Robert I. Paller has been a non-executive director of the Company since November 1, 2009. The Company has retained and continues to retain Smith, Gambrell & Russell, LLP (“SGR”), a law firm with which Mr. Paller holds a position. In the first three months of 2018 the Company incurred fees from SGR of $0.1 million (first three months of 2017 – $0.1 million). As at March 31, 2018, the amount due to SGR from the Company was $0.0 million (December 31, 2017 - $0.0 million).

Segement Reporting (Tables)

3 Months Ended

Mar. 31, 2018

Segment Reporting [Abstract]

Segment Reporting

The following tables analyze sales and other financial information by the Company’s reportable segments:


	Three Months Ended March 31
(in millions)	2018			2017
Net Sales:
Refinery and Performance	$	111.0		$	100.4
Other		32.4			26.0

Fuel Specialties		143.4			126.4

Personal Care		57.8			47.5
Home Care		34.2			26.9
Other		32.0			20.1

Performance Chemicals		124.0			94.5

Oilfield Services		92.9			66.5
Octane Additives		0.4			6.9

	$	360.7		$	294.3


	Three Months Ended March 31
(in millions)	2018			2017
Net sales:
Fuel Specialties	$	143.4		$	126.4
Performance Chemicals		124.0			94.5
Oilfield Services		92.9			66.5
Octane Additives		0.4			6.9

	$	360.7		$	294.3

Gross profit/(loss):
Fuel Specialties	$	48.5		$	46.1
Performance Chemicals		25.4			16.7
Oilfield Services		31.4			25.4
Octane Additives		(0.8	)		2.7

	$	104.5		$	90.9


Operating income/(loss):
Fuel Specialties	$	28.2		$	27.0
Performance Chemicals		12.1			6.0
Oilfield Services		3.0			3.0
Octane Additives		(1.4	)		2.0
Corporate costs		(13.0	)		(10.9	)
Foreign exchange loss on liquidation of subsidiary		0.0			(1.8	)

Total operating income	$	28.9		$	25.3

Summary of Segment Depreciation and Amortization

The following table presents a summary of the depreciation and amortization charges incurred by the Company’s reportable segments:


	Three Months Ended March 31
(in millions)	2018		2017
Depreciation:
Fuel Specialties	$	1.0	$	1.0
Performance Chemicals		2.7		2.2
Oilfield Services		1.5		1.6
Octane Additives		0.3		0.2
Corporate		0.3		0.2

	$	5.8	$	5.2

Amortization:
Fuel Specialties	$	0.0	$	0.2
Performance Chemicals		2.3		1.9
Oilfield Services		2.6		3.0
Corporate		1.8		1.8

	$	6.7	$	6.9

Earnings per Share (Tables)

3 Months Ended

Mar. 31, 2018

Earnings Per Share [Abstract]

Summary of Earnings Per Share

Per share amounts are computed as follows:


	Three Months Ended March 31
	2018		2017
Numerator (in millions):
Net income available to common stockholders	$	22.2	$	17.2

Denominator (in thousands):
Weighted average common shares outstanding		24,369		24,087
Dilutive effect of stock options and awards		205		440

Denominator for diluted earnings per share		24,574		24,527

Net income per share, basic:	$	0.91	$	0.71

Net income per share, diluted:	$	0.90	$	0.70

Goodwill (Tables)

3 Months Ended

Mar. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Summary of Goodwill

The following table summarizes goodwill at the balance sheet dates:


(in millions)	Total
At December 31, 2017
Gross cost ⁽¹⁾	$	598.3
Accumulated impairment losses		(236.5	)

Net book amount	$	361.8

Exchange effect		2.3
At March 31, 2018
Gross cost ⁽¹⁾	$	600.6
Accumulated impairment losses		(236.5	)

Net book amount	$	364.1

⁽¹⁾	Gross cost for 2018 and 2017 is net of $298.5 million of historical accumulated amortization.

Other Intangible Assets (Tables)

3 Months Ended

Mar. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Summary of Other Intangible Assets

The following table summarizes the other intangible assets movement year on year:


	Three Months Ended March 31
(in millions)	2018			2017
Gross cost at January 1	$	295.8		$	248.6
Acquisitions		0.0			33.5
Internally developed software		0.8			0.0
Exchange effect		1.2			0.1

Gross cost at March 31		297.8			282.2

Accumulated amortization at January 1		(132.5	)		(104.2	)
Amortization expense		(6.7	)		(6.9	)
Exchange effect		(0.3	)		0.1

Accumulated amortization at March 31		(139.5	)		(111.0	)

Net book amount at March 31	$	158.3		$	171.2

Schedule of Amortization Expense

Amortization expense


	Three Months Ended March 31
(in millions)	2018			2017
Product rights	$	(0.9	)	$	(0.9	)
Brand names		(0.3	)		(0.3	)
Technology		(0.9	)		(0.9	)
Customer relationships		(2.6	)		(2.6	)
Non-compete agreements		0.0			(0.2	)
Marketing related		0.0			(0.2	)
Internally developed software		(2.0	)		(1.8	)

Total	$	(6.7	)	$	(6.9	)

Pension and Post Employment Benefits (Tables)

3 Months Ended

Mar. 31, 2018

United Kingdom Plan [Member]

Plan Net Pension Credit

The following table shows the income statement effect recognized within other income, net:


	Three Months Ended March 31
(in millions)	2018			2017
Plan net pension credit/(charge):
Interest cost on projected benefit obligation		(3.9	)		(3.7	)
Expected return on plan assets		5.7			5.9
Amortization of prior service credit		0.3			0.3
Amortization of actuarial net losses		(0.5	)		(1.2	)

	$	1.6		$	1.3

German Plan [Member]

Plan Net Pension Credit

The following table shows the income statement effect recognized within other income and expense:


	Three Months Ended March 31
(in millions)	2018			2017
Plan net pension credit/(charge):
Interest cost on projected benefit obligation		(0.1	)		(0.1	)
Amortization of actuarial net losses		(0.1	)		(0.1	)

	$	(0.2	)	$	(0.2	)

Income Taxes (Tables)

3 Months Ended

Mar. 31, 2018

Income Tax Disclosure [Abstract]

Roll-Forward of Unrecognized Tax Benefits

A roll-forward of unrecognized tax benefits is as follows:


(in millions)	March 31, 2018		December 31, 2017
Opening balance at January 1	$	2.2	$	2.2
Additions for tax positions of prior periods		0.4		0.5
Reductions due to lapsed statute of limitations		0.0		(0.5	)

Closing balance	$	2.6	$	2.2

Long-Term Debt (Tables)

3 Months Ended

Mar. 31, 2018

Debt Disclosure [Abstract]

Schedule of Long-Term Debt

Long-term debt consists of the following:


(in millions)	March 31, 2018			December 31, 2017
Revolving credit facility	$	116.0		$	121.0
Term loan		99.0			99.0
Deferred finance costs		(1.4	)		(1.6	)

	$	213.6		$	218.4
Due within one year		(15.8	)		(15.8	)

Due after one year	$	197.8		$	202.6

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ 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 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21538-112644

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21521-112644

+ Details

Plant Closure Provisions (Tables)

3 Months Ended

Mar. 31, 2018

Restructuring and Related Activities [Abstract]

Movements in Plant Closure and Restructuring Provisions

Movements in the provisions are summarized as follows:


	Three Months Ended March 31
(in millions)	2018			2017
Total at January 1	$	46.1		$	39.5
Charge for the period		1.6			1.5
Utilized in the period		(0.9	)		(0.4	)
Exchange effect		0.1			0.0

Total at March 31		46.9			40.6
Due within one year		(4.2	)		(6.4	)

Due after one year	$	42.7		$	34.2

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

Carrying Amount and Fair Values of the Company's Financial Assets and Liabilities Measured on a Recurring Basis

The following table presents the carrying amount and fair values of the Company’s financial assets and liabilities measured on a recurring basis:


	March 31, 2018				December 31, 2017
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Assets
Non-derivatives:
Cash and cash equivalents	$	78.1	$	78.1	$	90.2	$	90.2
Derivatives (Level 1 measurement):
Other current and non-current assets:
Foreign currency forward exchange contracts		0.6		0.6		1.1		1.1
Interest rate swaps		2.6		2.6		1.5		1.5

Liabilities
Non-derivatives:
Long-term debt (including current portion)	$	213.6	$	213.6	$	218.4	$	218.4
Finance leases (including current portion)		5.2		5.2		5.9		5.9
Non-financial liabilities (Level 3 measurement):
Stock equivalent units		12.5		12.5		13.6		13.6

Stock-Based Compensation Plans (Tables)

3 Months Ended

Mar. 31, 2018

Stock Options Plan [Member]

Summary of Transactions of Company's Stock Option Plans

The following table summarizes the transactions of the Company’s stock option plans for the three months ended March 31, 2018:


	Number of Options			Weighted Average Exercise Price		Weighted Average Grant-Date Fair Value
Outstanding at December 31, 2017		357,666		$	13.74	$	35.69
Granted - at discount		71,227		$	0.00	$	57.53
- at market value		18,850		$	68.20	$	16.23
Exercised		(69,569	)	$	13.83	$	26.40
Forfeited		(11,874	)	$	19.69	$	27.17

Outstanding at March 31, 2018		366,300		$	13.66	$	40.97

Stock Equivalent Units [Member]

Summarizes Transactions of SEUs

The following table summarizes the transactions of the Company’s SEUs for the three months ended March 31, 2018:


	Number of SEUs			Weighted Average Exercise Price		Weighted Average Grant-Date Fair Value
Outstanding at December 31, 2017		400,342		$	3.10	$	46.65
Granted - at discount		101,278		$	0.00	$	57.44
- at market value		5,658		$	68.20	$	16.23
Exercised		(48,852	)	$	3.57	$	28.12
Forfeited		(16,554	)	$	1.40	$	37.14

Outstanding at March 31, 2018		441,872		$	3.23	$	51.14

Reclassifications out of Accumulated Other Comprehensive Loss (Tables)

3 Months Ended

Mar. 31, 2018

Equity [Abstract]

Summary of Reclassifications Out of Accumulated Other Comprehensive Loss

Reclassifications out of accumulated other comprehensive loss for the first three months of 2018 were:


(in millions) Details about AOCL Components	Amount Reclassified from AOCL			Affected Line Item in the Statement where Net Income is Presented
Defined benefit pension plan items:
Amortization of prior service credit	$	(0.3	)		See ⁽¹⁾ below
Amortization of actuarial net losses		0.5			See ⁽¹⁾ below

		0.2			Total before tax
		0.0			Income tax expense

Total reclassifications	$	0.2			Net of tax

⁽¹⁾	These items are included in other income and expense. See Note 6 of the Notes to the Condensed Consolidated Financial Statements for additional information.

Changes in Accumulated Other Comprehensive Loss

Changes in accumulated other comprehensive loss for the first three months of 2018, net of tax, were:


(in millions)	Derivative instruments		Defined Benefit Pension Plan Items			Cumulative Translation Adjustments			Total
Balance at December 31, 2017	$	1.2	$	(3.2	)	$	(36.5	)	$	(38.5	)

Other comprehensive income before reclassifications		0.9		0.0			6.4			7.3
Amounts reclassified from AOCL		0.0		0.2			0.0			0.2

Total other comprehensive income		0.9		0.2			6.4			7.5

Balance at March 31, 2018	$	2.1	$	(3.0	)	$	(30.1	)	$	(31.0	)

Segment Reporting - Additional Information (Detail)	3 Months Ended
Segment Reporting - Additional Information (Detail)	Mar. 31, 2018 Segment
Segment Reporting [Abstract]
Number of reportable segments	4

Segment Reporting - Segment Reporting (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Net sales	$ 360.7	$ 294.3
Gross profit/(loss)	104.5	90.9
Foreign exchange loss on liquidation of subsidiary	0.0	(1.8)
Operating income/(loss)	28.9	25.3
Operating Segments [Member] \| Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	143.4	126.4
Gross profit/(loss)	48.5	46.1
Operating income/(loss)	28.2	27.0
Operating Segments [Member] \| Fuel Specialties [Member] \| Refinery and Performance [Member]
Segment Reporting Information [Line Items]
Net sales	111.0	100.4
Operating Segments [Member] \| Fuel Specialties [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	32.4	26.0
Operating Segments [Member] \| Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	124.0	94.5
Gross profit/(loss)	25.4	16.7
Operating income/(loss)	12.1	6.0
Operating Segments [Member] \| Performance Chemicals [Member] \| Personal Care [Member]
Segment Reporting Information [Line Items]
Net sales	57.8	47.5
Operating Segments [Member] \| Performance Chemicals [Member] \| Home Care [Member]
Segment Reporting Information [Line Items]
Net sales	34.2	26.9
Operating Segments [Member] \| Performance Chemicals [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Net sales	32.0	20.1
Operating Segments [Member] \| Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	92.9	66.5
Gross profit/(loss)	31.4	25.4
Operating income/(loss)	3.0	3.0
Operating Segments [Member] \| Octane Additives [Member]
Segment Reporting Information [Line Items]
Net sales	0.4	6.9
Gross profit/(loss)	(0.8)	2.7
Operating income/(loss)	(1.4)	2.0
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Corporate costs	$ (13.0)	$ (10.9)

Segment Reporting - Summary of Segment Depreciation and Amortization (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Summary of segment depreciation and amortization
Depreciation	$ 5.8	$ 5.2
Amortization	6.7	6.9
Operating Segments [Member] \| Fuel Specialties [Member]
Summary of segment depreciation and amortization
Depreciation	1.0	1.0
Amortization	0.0	0.2
Operating Segments [Member] \| Performance Chemicals [Member]
Summary of segment depreciation and amortization
Depreciation	2.7	2.2
Amortization	2.3	1.9
Operating Segments [Member] \| Oilfield Services [Member]
Summary of segment depreciation and amortization
Depreciation	1.5	1.6
Amortization	2.6	3.0
Operating Segments [Member] \| Octane Additives [Member]
Summary of segment depreciation and amortization
Depreciation	0.3	0.2
Corporate, Non-Segment [Member]
Summary of segment depreciation and amortization
Depreciation	0.3	0.2
Amortization	$ 1.8	$ 1.8

Earnings Per Share - Summary of Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Numerator (in millions):
Net income available to common stockholders	$ 22.2	$ 17.2
Denominator (in thousands):
Weighted average common shares outstanding	24,369	24,087
Dilutive effect of stock options and awards	205	440
Denominator for diluted earnings per share	24,574	24,527
Net income per share, basic:	$ 0.91	$ 0.71
Net income per share, diluted:	$ 0.90	$ 0.70

Earnings Per Share - Additional Information (Detail) - shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share [Abstract]
Average number of anti-dilutive options excluded from the calculation of diluted earnings per share	18,468	9,422

Goodwill - Summary of Goodwill (Detail) $ in Millions	3 Months Ended
Goodwill - Summary of Goodwill (Detail) $ in Millions	Mar. 31, 2018 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Gross cost, beginning balance	$ 598.3
Accumulated impairment losses, beginning balance	(236.5)
Net book amount, beginning balance	361.8
Exchange effect	2.3
Gross cost, ending balance	600.6
Accumulated impairment losses, ending balance	(236.5)
Net book amount, ending balance	$ 364.1

Goodwill - Summary of Goodwill (Parenthetical) (Detail) - USD ($) $ in Millions	Mar. 31, 2018	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Historical accumulated amortization	$ 298.5	$ 298.5

Other Intangible Assets - Summary of Other Intangible Assets (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Gross cost at January 1	$ 295.8	$ 248.6
Acquisitions	0.0	33.5
Internally developed software	0.8	0.0
Exchange effect	1.2	0.1
Gross cost at March 31	297.8	282.2
Accumulated amortization at January 1	(132.5)	(104.2)
Amortization expense	(6.7)	(6.9)
Exchange effect	(0.3)	0.1
Accumulated amortization at March 31	(139.5)	(111.0)
Net book amount at March 31	$ 158.3	$ 171.2	$ 163.3

Other Intangible Assets - Schedule of Amortization Expense (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ (6.7)	$ (6.9)
Product Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	(0.9)	(0.9)
Brand Names [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	(0.3)	(0.3)
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	(0.9)	(0.9)
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	(2.6)	(2.6)
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	0.0	(0.2)
Marketing Related [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	0.0	(0.2)
Internally Developed Software [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ (2.0)	$ (1.8)

Pension and Post Employment Benefits - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Selling, General and Administrative Expenses [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost, total	$ 0.3	$ 0.2
Europe [Member] \| Foreign Pension Plan [Member] \| Performance Chemicals [Member]
Defined Benefit Plan Disclosure [Line Items]
Post-employment obligations European businesses	4.8		$ 4.7
Germany [Member] \| Foreign Pension Plan [Member] \| Fuel Specialties [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost, total	$ 0.0	$ 0.0

Pension and Post Employment Benefits - Plan Net Pension Credit (Detail) - Foreign Pension Plan [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
United Kingdom [Member]
Plan net pension credit/(charge):
Interest cost on projected benefit obligation	$ (3.9)	$ (3.7)
Expected return on plan assets	5.7	5.9
Amortization of prior service credit	0.3	0.3
Amortization of actuarial net losses	(0.5)	(1.2)
Net pension credit total	1.6	1.3
Germany [Member]
Plan net pension credit/(charge):
Interest cost on projected benefit obligation	(0.1)	(0.1)
Amortization of actuarial net losses	(0.1)	(0.1)
Net pension credit total	$ (0.2)	$ (0.2)

Income Taxes - Roll-Forward of Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Opening balance at January 1	$ 2.2	$ 2.2
Additions for tax positions of prior periods	0.4	0.5
Reductions due to lapsed statute of limitations	0.0	(0.5)
Closing balance	$ 2.6	$ 2.2

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Accrued net interest and penalties	$ 0.2
Increase in unrecognized tax benefits			$ 0.2
Unrecognized tax benefits, income tax interest and penalties accrued	0.5	$ 0.3	0.3
Unrecognized tax benefits, interest and penalties	3.1	2.5	2.5
Unrecognized tax benefit	$ 2.6	2.2	2.2	$ 2.2
Income tax examination, description	The Company and its U.S. subsidiaries remain open to examination by the IRS for years 2014 onwards under the statute of limitations. The Company’s subsidiaries in foreign tax jurisdictions are open to examination including France (2014 onwards), Germany (2015 onwards), Switzerland (2015 onwards) and the United Kingdom (2016 onwards).
Italian Tax Authorities [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefits, interest and penalties	$ 0.5
Unrecognized tax benefit		0.5	$ 0.5
Income tax interest expense	0.1	$ 0.2
Additional tax due	$ 0.4
France [Member]
Income Tax Contingency [Line Items]
Open tax year	2014
Germany [Member]
Income Tax Contingency [Line Items]
Open tax year	2015
Switzerland [Member]
Income Tax Contingency [Line Items]
Open tax year	2015
United Kingdom [Member]
Income Tax Contingency [Line Items]
Open tax year	2016
Italy [Member] \| Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2011
Italy [Member] \| Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2013

Long-Term Debt - Schedule of Long-Term Debt (Detail) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Deferred finance costs	$ (1.4)	$ (1.6)
Long-term debt	213.6	218.4
Due within one year	(15.8)	(15.8)
Due after one year	197.8	202.6
Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt	99.0	99.0
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt	$ 116.0	$ 121.0

Plant Closure Provisions - Movements in Plant Closure and Restructuring Provisions (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Beginning Balance	$ 46.1	$ 39.5
Charge for the period	1.6	1.5
Utilized in the period	(0.9)	(0.4)
Exchange effect	0.1	0.0
Ending Balance	46.9	40.6
Due within one year	(4.2)	(6.4)	$ (5.2)
Due after one year	$ 42.7	$ 34.2	$ 40.9

Fair Value Measurements - Carrying Amount and Fair Values of the Company's Financial Assets and Liabilities Measured on a Recurring Basis (Detail) - Recurring [Member] - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Carrying Amount [Member]
Non-derivatives:
Cash and cash equivalents	$ 78.1	$ 90.2
Non-derivatives:
Long-term debt (including current portion)	213.6	218.4
Finance leases (including current portion)	5.2	5.9
Carrying Amount [Member] \| Derivatives (Level 1 Measurement) [Member] \| Foreign Currency Forward Exchange Contracts [Member]
Derivatives (Level 1 measurement):
Derivative asset	0.6	1.1
Carrying Amount [Member] \| Derivatives (Level 1 Measurement) [Member] \| Interest Rate Swaps [Member]
Derivatives (Level 1 measurement):
Derivative asset	2.6	1.5
Carrying Amount [Member] \| Non-financial Assets and Liabilities (Level 3 Measurement) [Member]
Non-financial liabilities (Level 3 measurement):
Stock equivalent units	12.5	13.6
Fair Value [Member]
Non-derivatives:
Cash and cash equivalents	78.1	90.2
Non-derivatives:
Long-term debt (including current portion)	213.6	218.4
Finance leases (including current portion)	5.2	5.9
Fair Value [Member] \| Derivatives (Level 1 Measurement) [Member] \| Foreign Currency Forward Exchange Contracts [Member]
Derivatives (Level 1 measurement):
Derivative asset	0.6	1.1
Fair Value [Member] \| Derivatives (Level 1 Measurement) [Member] \| Interest Rate Swaps [Member]
Derivatives (Level 1 measurement):
Derivative asset	2.6	1.5
Fair Value [Member] \| Non-financial Assets and Liabilities (Level 3 Measurement) [Member]
Non-financial liabilities (Level 3 measurement):
Stock equivalent units	$ 12.5	$ 13.6

Derivative Instruments and Risk Management - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Maximum [Member]
Derivative [Line Items]
Maturity period of foreign currency forward exchange contracts	12 months
Not Designated as Hedging Instrument [Member] \| Foreign Currency Forward Exchange Contracts [Member] \| Other net income/(expense) [Member]
Derivative [Line Items]
Amount of gain/(loss) recognized in income	$ (0.5)	$ (0.5)
Designated as Hedging Instrument [Member] \| Interest Rate Swaps [Member] \| Accumulated Other Comprehensive Loss [Member]
Derivative [Line Items]
Amount of gain/(loss) recognized in income	$ 1.1	$ 0.3

Commitments and Contingencies - Additional Information (Detail) $ in Millions	Mar. 31, 2018 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Guarantees	$ 5.2

Stock-Based Compensation Plans - Summary of Transactions of the Company's Stock Option Plans (Detail) - Stock Options Plan [Member]	3 Months Ended
	Mar. 31, 2018 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Number of Options, Beginning balance \| shares	357,666
Exercised, Number of Options \| shares	(69,569)
Forfeited, Number of Options \| shares	(11,874)
Outstanding, Number of Options, Ending balance \| shares	366,300
Outstanding, Weighted Average Exercise Price, Beginning balance	$ 13.74
Exercised, Weighted Average Exercise Price	13.83
Forfeited, Weighted Average Exercise Price	19.69
Outstanding, Weighted Average Exercise Price, Ending balance	13.66
Outstanding, Weighted Average Grant-Date Fair Value	35.69
Exercised	26.40
Forfeited, Weighted Average Grant-Date Fair Value	27.17
Outstanding, Weighted Average Grant-Date Fair Value	$ 40.97
Discount [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of Options \| shares	71,227
Granted, Weighted Average Exercise Price	$ 0.00
Granted, Weighted Average Grant-Date Fair Value	$ 57.53
Market Value [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of Options \| shares	18,850
Granted, Weighted Average Exercise Price	$ 68.20
Granted, Weighted Average Grant-Date Fair Value	$ 16.23

Stock-Based Compensation Plans - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option compensation	$ 0.8	$ 1.0
Stock Options Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number exercisable and fully vested	49,272
Fully vested stock options with performance conditions attached	2,672
Stock option compensation	$ 0.8	1.0
Total intrinsic value exercised	1.9	1.8
Total compensation cost related to non-vested stock options not yet recognized	$ 8.9
Expected compensation cost recognized over the weighted-average period	2 years 3 months 11 days
Stock Equivalent Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fully vested stock options with performance conditions attached	43,834
Total intrinsic value exercised	$ 1.6	0.9
Expected compensation cost recognized over the weighted-average period	2 years 1 month 13 days
Number of exercisable SEUs	51,863
Compensation cost	$ 1.2	$ 0.9

Stock-Based Compensation Plans - Summarizes Transactions of SEUs (Detail) - Stock Equivalent Units [Member]	3 Months Ended
	Mar. 31, 2018 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Weighted Average Exercise Price, Beginning balance	$ 3.10
Granted at discount, Weighted Average Exercise Price	0.00
Granted at market value, Weighted Average Exercise Price	68.20
Exercised, Weighted Average Exercise Price	3.57
Forfeited, Weighted Average Exercise Price	1.40
Outstanding, Weighted Average Exercise Price, Ending balance	$ 3.23
Outstanding, Number of SEUs, Beginning balance \| shares	400,342
Granted at discount, Number of SEUs \| shares	101,278
Granted at market value, Number of SEUs \| shares	5,658
Exercised, Number of SEUs \| shares	(48,852)
Forfeited, Number of SEUs \| shares	(16,554)
Outstanding, Number of SEUs, Ending balance \| shares	441,872
Outstanding, Weighted Average Grant-Date Fair Value	$ 46.65
Granted at discount, Weighted Average Grant-Date Fair Value	57.44
Granted at market value, Weighted Average Grant-Date Fair Value	16.23
Exercised, Weighted Average Grant-Date Fair Value	28.12
Forfeited, Weighted Average Grant-Date Fair Value	37.14
Outstanding, Weighted Average Grant-Date Fair Value	$ 51.14

Reclassifications out of Accumulated Other Comprehensive Loss - Summary of Reclassifications out of Accumulated Other Comprehensive Loss (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications	$ (0.2)
Defined Benefit Pension Plan Items [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications	(0.2)
Reclassification Out of Accumulated Other Comprehensive Income/(Loss) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	0.2
Income tax expense	0.0
Total reclassifications	0.2
Reclassification Out of Accumulated Other Comprehensive Income/(Loss) [Member] \| Defined Benefit Pension Plan Items [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of prior service credit	(0.3)
Amortization of actuarial net losses	$ 0.5

Reclassifications out of Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 793.9
Other comprehensive income before reclassifications	7.3
Amounts reclassified from AOCL	0.2
Total other comprehensive income	7.5	$ 4.5
Ending Balance	824.4
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(38.5)
Ending Balance	(31.0)
Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	1.2
Other comprehensive income before reclassifications	0.9
Amounts reclassified from AOCL	0.0
Total other comprehensive income	0.9
Ending Balance	2.1
Defined Benefit Pension Plan Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(3.2)
Other comprehensive income before reclassifications	0.0
Amounts reclassified from AOCL	0.2
Total other comprehensive income	0.2
Ending Balance	(3.0)
Foreign Currency Translation Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(36.5)
Other comprehensive income before reclassifications	6.4
Amounts reclassified from AOCL	0.0
Total other comprehensive income	6.4
Ending Balance	$ (30.1)

Recently Issued Accounting Pronouncements - Additional Information (Detail) - Accounting Standards Update 2017-07 [Member] $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Operating Income (Loss) [Member]
Change in Accounting Estimate [Line Items]
Impact on operating results	$ (1.1)
Other Nonoperating Income (Expense) [Member]
Change in Accounting Estimate [Line Items]
Impact on operating results	$ 1.1

Related Party Transactions - Additional Information (Detail) - Smith, Gambrell & Russell, LLP [Member] - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
Related Party Transaction [Line Items]
Fees payable to Smith, Gambrell & Russell	$ 0.1		$ 0.1
Amount due to Smith, Gambrell & Russell	$ 0.0	$ 0.0