Innospec (IOSP) 10-K 22 Feb 23 2022 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Feb. 15, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Document Annual Report	true
Document Transition Report	false
Current Fiscal Year End Date	--12-31
Document Period End Date	Dec. 31, 2022
Entity File Number	1-13879
Entity Registrant Name	INNOSPEC INC.
Entity Central Index Key	0001054905
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	98-0181725
Entity Address, Postal Zip Code	80112
City Area Code	303
Local Phone Number	792 5554
Security Exchange Name	NASDAQ
Title of 12(b) Security	Common stock
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		24,765,534
Entity Address, Address Line One	8310 South Valley Highway
Entity Address, Address Line Two	Suite 350
Entity Address, City or Town	Englewood
Entity Address, State or Province	CO
Trading Symbol	IOSP
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Entity Public Float			$ 1,409
ICFR Auditor Attestation Flag	true
Auditor Name	PricewaterhouseCoopers LLP
Auditor Firm ID	876
Auditor Location	Manchester, United Kingdom

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
Net sales	$ 1,963.7	$ 1,483.4	$ 1,193.1
Cost of goods sold	(1,377)	(1,048.5)	(850.4)
Gross profit	586.7	434.9	342.7
Operating expenses:
Selling, general and administrative	(360.7)	(267.2)	(237)
Research and development	(38.7)	(37.4)	(30.9)
Restructuring charge	0	0	(21.3)
Impairment of intangible assets	0	0	(19.8)
Profit on disposal	0	1.8	0
Total operating expenses	(399.4)	(302.8)	(309)
Operating income	187.3	132.1	33.7
Other (expense)/income, net	(1.6)	3.8	7.8
Interest expense, net	(1.1)	(1.5)	(1.8)
Income before income tax expense	184.6	134.4	39.7
Income tax expense	(51.6)	(41.3)	(11)
Net income	$ 133	$ 93.1	$ 28.7
Earnings per share:
Basic	$ 5.37	$ 3.78	$ 1.17
Diluted	$ 5.32	$ 3.75	$ 1.16
Weighted average shares outstanding (in thousands):
Basic	24,787	24,647	24,563
Diluted	24,982	24,854	24,779

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 133	$ 93.1	$ 28.7
Changes in cumulative translation adjustment, net of tax of $5.5 million, $2.0 million and $3.9 million, respectively	(29.2)	(20.2)	23.7
Amortization of prior service cost/(credit), net of tax of $(0.1) million, $(0.1) million and $0.1 million, respectively	0.4	0.2	(0.4)
Amortization of actuarial net losses, net of tax of $(0.1) million, $(0.4) million and $(0.2) million, respectively	0.4	2.2	1.5
Actuarial net gains/(losses) arising during the year, net of tax of $24.0 million, $(9.0) million and $1.9 million, respectively	(69.9)	28.2	(7.7)
Total comprehensive income	$ 34.7	$ 103.5	$ 45.8

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Changes in cumulative translation adjustment, tax	$ 5.5	$ 2	$ 3.9
Amortization of prior service credit, tax	(0.1)	(0.1)	0.1
Amortization of actuarial net losses, tax	(0.1)	(0.4)	(0.2)
Actuarial net gains, tax	$ 24	$ (9)	$ 1.9

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 147.1	$ 141.8
Trade and other accounts receivable (less allowances of $7.7 million and $5.1 million, respectively)	334.6	284.5
Inventories (less allowances of $27.1 million and $25.4 million, respectively):
Finished goods	259.3	188.3
Raw materials	113.8	89.3
Total inventories	373.1	277.6
Prepaid expenses	14.1	18
Prepaid income taxes	3.3	5.8
Other current assets	0.4	0.4
Total current assets	872.6	728.1
Net property, plant and equipment	220.9	214.4
Operating leases right-of-use assets	45.3	35.4
Goodwill	358.8	364.3
Other intangible assets	45	57.5
Deferred tax assets	5.9	6.4
Pension asset	48.1	159.8
Other non-current assets	7.1	5
Total assets	1,603.7	1,570.9
Current liabilities:
Accounts payable	165.3	148.7
Accrued liabilities	202.9	166.5
Current portion of finance leases	0	0.1
Current portion of operating lease liabilities	13.9	12.4
Current portion of plant closure provisions	5.3	5.2
Current portion of accrued income taxes	18.4	3.7
Total current liabilities	405.8	336.6
Operating lease liabilities, net of current portion	31.4	23.1
Plant closure provisions, net of current portion	51.9	51.3
Accrued income taxes, net of current portion	21	30.6
Unrecognized tax benefits, net of current portion	13.4	16.3
Deferred tax liabilities	26.2	60.8
Pension liabilities and post-employment benefits	12.2	17.8
Other non-current liabilities	1.4	1.4
Total liabilities	563.3	537.9
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	354.1	346.7
Treasury stock (4,788,966 and 4,780,806 shares at cost, respectively)	(95.4)	(90.6)
Retained earnings	924.2	822.9
Accumulated other comprehensive loss	(145.2)	(46.9)
Total Innospec stockholders' equity	1,038	1,032.4
Non-controlling interest	2.4	0.6
Total equity	1,040.4	1,033
Total liabilities and equity	$ 1,603.7	$ 1,570.9

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Allowances for doubtful accounts	$ 7.7	$ 5.1
Inventory allowances	$ 27.1	$ 25.4
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	4,788,966	4,780,806

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash Flows from Operating Activities
Net income	$ 133	$ 93.1	$ 28.7
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	40.1	42.7	46
Impairment of intangible assets	0	0	19.8
Impairment of tangible assets	0	0	2
Deferred taxes	(5.5)	6.4	(2.5)
Profit on disposal	0	(1.8)	0
Non-cash income of defined benefit pension plans	(2.5)	(3.5)	(4)
Stock option compensation	6.7	4.4	5.8
Changes in assets and liabilities, net of effects of acquired and divested companies:
Trade and other accounts receivable	(55.5)	(70.3)	74.4
Inventories	(98.5)	(62)	25.5
Prepaid expenses	4.6	(3.5)	(1)
Accounts payable and accrued liabilities	54.2	90.2	(45.9)
Plant closure provisions	1.1	(1.4)	8.5
Accrued income taxes	9.4	(3.2)	(10.3)
Unrecognized tax benefits	(2.9)	0.3	(0.4)
Other assets and liabilities	(2.5)	1.8	(0.7)
Net cash provided by operating activities	81.7	93.2	145.9
Cash Flows from Investing Activities
Capital expenditures	(39.6)	(39.1)	(29.7)
Proceeds on disposal of property, plant and equipment	0.2	2.9	0
Internally developed software	(2.7)	0	0
Net cash used in investing activities	(42.1)	(36.2)	(29.7)
Cash Flows from Financing Activities
Non-controlling interest	1.8	0.1	0.1
Proceeds from revolving credit facility	0	0	15
Repayments of revolving credit facility	0	0	(75)
Repayment of finance leases	(0.1)	(0.6)	(1.1)
Refinancing costs	0	0	(0.3)
Dividend paid	(31.7)	(28.8)	(25.6)
Issue of treasury stock	2.2	10.1	2.2
Repurchase of common stock	(5.9)	(0.8)	(2.1)
Net cash used in financing activities	(33.7)	(20)	(86.8)
Effect of foreign currency exchange rate changes on cash	(0.6)	(0.5)	0.2
Net change in cash and cash equivalents	5.3	36.5	29.6
Cash and cash equivalents at beginning of year	141.8	105.3	75.7
Cash and cash equivalents at end of year	$ 147.1	$ 141.8	$ 105.3

Consolidated Statements of Equi

Consolidated Statements of Equity - 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, 2019	$ 918.9	$ 0.3	$ 330.4	$ (93.3)	$ 755.5	$ (74.4)	$ 0.4
Net income	28.7				28.7
Dividend paid	(25.6)				(25.6)
Changes in cumulative translation adjustment, net of tax	23.7					23.7
Share of net income	0.1						0.1
Treasury stock re-issued	2		(0.1)	2.1
Treasury stock repurchased	(2.1)			(2.1)
Stock option compensation	5.8		5.8
Amortization of prior service cost, net of tax	(0.4)					(0.4)
Amortization of actuarial net losses, net of tax	1.5					1.5
Actuarial net gains (losses) arising during the year, net of tax	(7.7)					(7.7)
Ending Balance at Dec. 31, 2020	944.9	0.3	336.1	(93.3)	758.6	(57.3)	0.5
Net income	93.1				93.1
Dividend paid	(28.8)				(28.8)
Changes in cumulative translation adjustment, net of tax	(20.2)					(20.2)
Share of net income	0.1						0.1
Treasury stock re-issued	9.7		6.2	3.5
Treasury stock repurchased	(0.8)			(0.8)
Stock option compensation	4.4		4.4
Amortization of prior service cost, net of tax	0.2					0.2
Amortization of actuarial net losses, net of tax	2.2					2.2
Actuarial net gains (losses) arising during the year, net of tax	28.2					28.2
Ending Balance at Dec. 31, 2021	1,033	0.3	346.7	(90.6)	822.9	(46.9)	0.6
Net income	133				133
Dividend paid	(31.7)				(31.7)
Changes in cumulative translation adjustment, net of tax	(29.2)					(29.2)
Non-controlling interest investment	1.8						1.8
Treasury stock re-issued	1.7		0.7	1
Treasury stock repurchased	(5.8)			(5.8)
Stock option compensation	6.7		6.7
Amortization of prior service cost, net of tax	0.4					0.4
Amortization of actuarial net losses, net of tax	0.4					0.4
Actuarial net gains (losses) arising during the year, net of tax	(69.9)					(69.9)
Ending Balance at Dec. 31, 2022	$ 1,040.4	$ 0.3	$ 354.1	$ (95.4)	$ 924.2	$ (145.2)	$ 2.4

Consolidated Statements of Eq_2

Consolidated Statements of Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement of Stockholders' Equity [Abstract]
Dividend paid, per share	$ 1.28	$ 1.16	$ 1.04

Nature of Operations

Nature of Operations	12 Months Ended
	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	Note 1. Nature of Operations Innospec develops, manufactures, blends, markets and supplies a wide range of specialty chemicals to markets in the Americas, Europe, the Middle East, Africa and Asia-Pacific. Our Performance Chemicals business creates innovative technology-based solutions for our customers in the personal care, home care, agrochemical, mining and industrial markets. Our Fuel Specialties business specializes in manufacturing and supplying fuel additives that improve fuel efficiency, boost engine performance and reduce harmful emissions. Our Oilfield Services business supplies drilling, completion and production chemicals which make exploration and production more effective, cost-efficient and environmentally friendly.

Accounting Policies

Accounting Policies	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Accounting Policies	Note 2. Accounting Policies Basis of preparation: Use of estimates: Revenue recognition: on-demand While some of our customers have payment terms beyond 30 days, we do not provide extended payment terms of a year or more, nor do our contracts include a financing component. Some of our contracts include variable consideration in the form of rebates. We record rebates at the point of sale as a reduction in sales when we can reasonably estimate the amount of the rebate. The estimates are based on our best judgment at the time of sale, which includes anticipated as well as historical performance. Taxes assessed by a governmental authority which are concurrent with sales to our customers, including sales, use, value-added, and revenue-related excise taxes, are collected by us from the customer and are not included in net sales, but are reflected in accrued liabilities until remitted to the appropriate governmental authority. When we are responsible for shipping and handling costs after title has transferred, we account for those as fulfilment costs and include them in cost of goods sold. Components of net sales: Components of cost of goods sold: non-recoverable Components of selling, general and administrative expenses: Research and development expenses: Earnings per share: Foreign currencies: where the U.S. dollar is the functional currency no gains or losses on translation occur, and gains or losses on monetary assets relating to currencies other than the U.S. dollar are taken to the income statement in other income/(expense), net. Gains and losses on intercompany foreign currency loans which are long-term in nature, which the Company does not intend to settle in the foreseeable future, are also recorded in accumulated other comprehensive loss. Other foreign exchange gains or losses are also included in other income, net in the income statement. Share Business combinations: The determination of the fair values of certain assets and liabilities are usually based on significant estimates provided by management, such as forecast revenue or profit. In determining the fair value of intangible assets, an income approach is generally used and may incorporate the use of a discounted cash flow method. In applying the discounted cash flow method, the estimated future cash flows and residual values for each intangible asset are discounted to a present value using a discount rate appropriate to the business being acquired. These cash flow projections are based on management’s estimates of economic and market conditions including revenue growth rates, operating margins, capital expenditures and working capital requirements. Cash equivalents: Trade and other accounts receivable: The Company is exposed to credit losses primarily through sales of products. The Company’s expected loss allowance methodology for trade and other accounts receivable is developed using historical collection experience, current and future economic and market conditions and a review of the current status of customers’ receivables. Due to the short-term nature of such receivables, the estimate of accounts receivable amounts that may not be collected is based on aging of the accounts receivable balances and the financial condition of customers. Additionally, a further allowance is included to account for the Company’s historic track record of credit losses, for balances which are not aged sufficiently to be considered under the aging based approach . Inventories: Property, plant and equipment: Buildings 7 to 25 years Equipment 3 to 10 years Goodwill: Initially we perform a qualitative assessment to determine whether it is more likely than not (that is, a likelihood of more than 50 percent) that the fair value of a reportable segment is less than the carrying amount prior to performing a quantitative goodwill impairment test. The annual measurement date for impairment assessment of the goodwill relating to the Performance Chemicals, Fuel Specialties and Oilfield Services segments is December 31 each year. Factors utilized in the qualitative assessment process include macroeconomic conditions, industry and market considerations, cost factors, overall financial performance and Company specific events. If a quantitative test is required, we assess the fair value based on projected post-tax projected operating margins, changes in working capital and discount rates. We would develop these assumptions by considering recent financial performance and industry growth estimates. O ther intangible assets: . In order to facilitate testing for potential impairment the Company groups together assets at the lowest possible level for which cash flow information is available. Undiscounted future cash flows expected to result from the asset groups are compared with the carrying value of the assets and, if such cash flows are lower, an impairment loss may be recognized. The amount of the impairment loss is the difference between the fair value and the carrying value of the assets. Fair values are determined using post-tax non-cash The estimated useful lives of the major classes of assets are as follows: Technology 10 to 17 years Customer lists 10 to 15 years Brand names 5 to 10 years Product rights 9 to 10 years Internally developed software 3 to 10 years Marketing related 11 years Leases: right-of-use non-current) non-current) Operating lease ROU assets and operating lease liabilities are recognized based on the present value of future lease payments over the remaining lease term. Very few of our leases have renewal options or early termination break clauses, but where they do we have assessed the term of the lease based on any options being exercised only if they are reasonably certain. As most of our leases do not provide an implicit interest rate, we use our incremental borrowing rate based on the information available at point of recognition in determining the present value of future payments. The operating lease ROU asset excludes lease incentives and initial direct costs incurred. Lease expense for lease payments is recognized on a straight-line basis over the lease term unless payments are variable per the agreement. We do not separate related non-lease We do not recognize a ROU asset or operating lease liability for short-term leases (with a length of one year or less), and any associated cost is recognized, as incurred, through the income statement . Deferred finance costs: Impairment of long-lived assets: post-tax Derivative instruments: From non-current earnings. Plant closure provisions: This Movements in the Projected Benefit Obligation (“PBO”) are dependent on our assumptions in respect of the discount rate, annual member mortality rates, future return on assets and future inflation. Income taxes: and extend to environmental liabilities that result from other-than-normal operation of long-lived assets, for example pollution. Remediation costs relate to asset retirement obligations at our current and former manufacturing sites following retirement of the long-lived assets, linked to their normal operation. We recognize environmental liabilities when they are probable and the costs can be reasonably estimated, and asset retirement obligations when there is an obligation based on a legal requirement , including those arising from a The Company must comply with environmental legislation in the countries in which it operates or has operated in and annually reassesses the program of work required. This includes estimating the credit-adjusted risk free rate and the timing and cost of performing the remediation work. Management receives input from specialists to develop these estimates and assumptions utilizing the latest information available together with experience of recent costs. While we believe our assumptions for the liabilities are reasonable, they are subjective estimates and it is possible that variations in any of the assumptions will result in materially different calculations to the liabilities we have reported. Costs of future obligations are discounted to their present values using the Company’s credit-adjusted risk-free rate. Pension plans and other post-employment benefits: year-end. In May 2022, the Trustees of the United Kingdom defined benefit pension plan (“UK Plan”) entered into an agreement with Legal and General Assurance Society Limited to acquire an insurance policy that operates as an investment asset, with the intent of matching the remaining uninsured part of the UK Plan’s future cash outflow arising from the accrued pension liabilities of members. Such an arrangement is commonly termed as a “buy-in”. buy-in buy-in

Segment Reporting and Geographi

Segment Reporting and Geographical Area Data	12 Months Ended
	Dec. 31, 2022
Segment Reporting [Abstract]
Segment Reporting	Note 3. Segment Reporting and Geographical Area Data The Performance Chemicals, Fuel Specialties and Oilfield Services segments operate in markets where we actively seek growth opportunities although their ultimate customers are different. The Octane Additives segment ceased trading and is no longer a reporting segment from July 1, 2020. Our Performance Chemicals segment provides effective technology-based solutions for our customers’ processes or products focused in the personal care, home care, agrochemical, mining and other industrial markets. Our Fuel Specialties segment develops, manufactures, blends, markets and supplies a range of specialty chemicals products used as additives to a wide range of fuels. Our Oilfield Services segment develops and markets chemical solutions for fracturing, drilling, stimulation and completion operations, products for oil and gas production and transport which aid flow assurance and maintain asset integrity. The Octane Additives business has ceased trading and is no longer a reporting segment from July 1, 2020 as the production of TEL for use in motor gasoline has finished. Legacy costs related to these operations are now being recorded as operating expenses within corporate costs. In 2022, the Company had a significant customer in the Oilfield Services segment which accounted for $222.2 million (11.3%) of our net group sales. The Company evaluates the performance of its segments based on operating income. The following table analyzes sales and other financial information by the Company’s reportable segments: (in millions) 2022 2021 2020 Net Sales: Personal Care $ 393.3 $ 296.1 $ 231.4 Home Care 94.2 93.0 87.0 Other 152.2 136.2 107.0 Performance Chemicals 639.7 525.3 425.4 Refinery and Performance 552.6 445.3 372.9 Other 177.6 173.0 139.8 Fuel Specialties 730.2 618.3 512.7 Oilfield Services 593.8 339.8 255.0 $ 1,963.7 $ 1,483.4 $ 1,193.1 Operating income/(expense): Performance Chemicals $ 95.3 $ 70.9 $ 54.8 Fuel Specialties 121.7 104.6 84.5 Oilfield Services 41.7 10.4 (9.5 ) Octane Additives — — (2.8 ) Corporate costs (71.4 ) (55.6 ) (52.2 ) Restructuring charge — — (21.3 ) Impairment of intangible assets — — (19.8 ) Profit on disposal — 1.8 — Total operating income $ 187.3 $ 132.1 $ 33.7 Identifiable assets at year-end: Performance Chemicals $ 610.4 $ 469.5 $ 391.5 Fuel Specialties 500.6 571.3 509.7 Oilfield Services 297.8 230.8 210.8 Corporate 194.9 299.3 285.4 $ 1,603.7 $ 1,570.9 $ 1,397.4 The Company includes within the corporate costs line item the costs of: • managing the group as a company with securities listed on the NASDAQ and registered with the SEC; • the President/CEO’s office, group finance, group human resources, group legal and compliance counsel, and investor relations; • running the corporate offices in the U.S. and Europe; • the corporate development function since they do not relate to the current trading activities of our other reporting segments; and • the corporate share of the information technology, product technology, safety, health, environment, accounting and human resources departments. The following tables analyze sales and other financial information by location: (in millions) 2022 2021 2020 Net sales by source: United States & North America $ 1,244.9 $ 821.6 $ 642.4 United Kingdom 932.5 811.9 689.1 Rest of Europe 116.9 115.6 83.4 Rest of World 67.7 66.4 45.6 Sales between areas (398.3 ) (332.1 ) (267.4 ) $ 1,963.7 $ 1,483.4 $ 1,193.1 Income before income taxes: United States & North America $ 109.1 $ 54.6 $ — United Kingdom 42.9 46.1 16.9 Rest of Europe 25.5 26.4 19.7 Rest of World 7.1 7.3 3.1 $ 184.6 $ 134.4 $ 39.7 Long-lived assets at year-end: United States & North America $ 147.0 $ 137.3 $ 141.0 United Kingdom 50.6 55.4 61.3 Rest of Europe 112.4 112.0 123.2 Rest of World 0.2 0.2 0.2 $ 310.2 $ 304.9 $ 325.7 Identifiable assets at year-end: United States & North America $ 570.9 $ 464.9 $ 368.8 United Kingdom 462.3 533.7 455.8 Rest of Europe 164.0 164.7 171.0 Rest of World 47.7 43.3 30.6 Goodwill 358.8 364.3 371.2 $ 1,603.7 $ 1,570.9 $ 1,397.4 Sales by geographical area are reported by source, being where the transactions originated. Intercompany sales are priced using an appropriate pricing methodology and are eliminated in the consolidated financial statements. Identifiable assets are those directly associated with the operations of the geographical area. Goodwill has not been allocated by geographical location on the grounds that it would be impracticable to do so.

Earnings per Share

Earnings per Share	12 Months Ended
	Dec. 31, 2022
Earnings Per Share [Abstract]
Earnings per Share	Note 4. 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: 2022 2021 2020 Numerator (in millions): Net income available to common stockholders $ 133.0 $ 93.1 $ 28.7 Denominator (in thousands): Weighted average common shares outstanding 24,787 24,647 24,563 Dilutive effect of stock options and awards 195 207 216 Denominator for diluted earnings per share 24,982 24,854 24,779 Net income per share, basic: $ 5.37 $ 3.78 $ 1.17 Net income per share, diluted: $ 5.32 $ 3.75 $ 1.16 In 2022, 2021 and 2020 the average number of anti-dilutive options excluded from the calculation of diluted earnings per share were 79,145, 18,378 and 17,980 respectively.

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2022
Restructuring Charges [Abstract]
Restructuring	Note 5. Restructuring During 2020, the Company recorded a charge of $21.3 million for the restructuring of its Octane Additives segment in line with the end of the manufacturing and sale of TEL for use in motor gasoline. As a result, the Octane Additives segment ceased trading and is no longer a reporting segment from July 1, 2020. Production of TEL will continue for sales of our AvGas product line, as reported within our Fuel Specialties segment. The restructuring charge down-sizing

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Note 6. Property, Plant and Equipment Property, plant and equipment consists of the following: (in millions) 2022 2021 Land $ 20.6 $ 20.7 Buildings 68.7 69.5 Equipment 377.5 371.5 Work in progress 45.7 23.7 Total gross cost 512.5 485.4 Less accumulated depreciation and impairment (291.6 ) (271.0 ) Total net book value $ 220.9 $ 214.4 Of the total net book value of equipment at December 31, 2022, $0.0 million are in respect of assets held under finance leases (2021 – $0.5 million). Depreciation charges were $25.7 million, $26.3 million and $24.7 million in 2022, 2021 and 2020, respectively.

Leases

Leases	12 Months Ended
	Dec. 31, 2022
Leases [Abstract]
Leases	Note 7. Leases We have operating and finance leases for toll manufacturing facilities, warehouse storage, land, buildings, plant and equipment. Our leases have remaining lease terms of up to 23 years, some of which include options to terminate the leases within 1 year. The components of lease expense were as follows: (in millions) Twelve Months Twelve Months 2022 2021 Finance lease cost: Amortization of right-of-use $ — $ 0.5 Interest on lease liabilities — — Total finance lease cost — 0.5 Operating lease cost 15.6 13.8 Short-term lease cost 7.2 3.8 Variable lease cost 0.3 0.3 Total lease cost $ 23.1 $ 18.4 Supplemental cash flow information related to leases is as follows: (in millions) Twelve Months Twelve Months 2022 2021 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 23.1 $ 18.1 Operating cash flows from finance leases 0.1 0.5 Finance cash flows from finance leases — — Right-of-use Operating leases $ 14.9 $ 5.2 Finance leases — — Supplemental balance sheet information related to leases is as follows: (in millions except lease term and discount rate) December 31 December 31 Operating leases: Operating lease right-of-use $ 45.3 $ 35.4 Current portion of operating lease liabilities $ 13.9 $ 12.4 Operating lease liabilities, net of current portion 31.4 23.1 Total operating lease liabilities $ 45.3 $ 35.5 Finance leases: Property, plant and equipment at cost $ — $ 5.0 Accumulated depreciation — (4.5 ) Net property, plant and equipment $ — $ 0.5 Current portion finance leases $ — $ 0.1 Finance leases, net of current portion — — Total finance lease liabilities $ — $ 0.1 (in millions except lease term and discount rate) December 31 December 31 Weighted average remaining lease term: Operating leases 5.5 years 4.9 years Finance leases — 0.5 years Weighted average discount rate: Operating leases 2.6 % 2.5 % Finance leases — 2.5 % Maturities of lease liabilities were as follows as at December 31, 2022: (in millions) Operating Within one year $ 14.3 Year two 8.9 Year three 6.4 Year four 5.2 Year five 1.5 Thereafter 13.5 Total lease payments 49.8 Less imputed interest (4.5 ) Total $ 45.3 As of December 31, 2022, additional operating and finance leases that have not yet commenced are $2.7 million. Future lease payment for all non-cancellable (in millions) Operating Finance Within one year $ 12.5 $ 0.1 Year two 9.0 — Year three 6.0 — Year four 3.9 — Year five 3.1 — Thereafter 3.2 — Total lease payments 37.7 0.1 Less imputed interest (2.2 ) — Total $ 35.5 $ 0.1 As of December 31, 2021, additional operating and finance leases that have not yet commenced are $8.8 million.

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Note 8. Goodwill The following table analyzes goodwill movement for 2022 and 2021. (in millions) Performance Fuel Oilfield Total At December 31, 2020 Gross cost $ 118.5 $ 207.9 $ 44.8 $ 371.2 Accumulated impairment losses — — — — Net book amount $ 118.5 $ 207.9 $ 44.8 $ 371.2 Exchange effect (6.6 ) (0.3 ) — (6.9 ) At December 31, 2021 Gross cost $ 111.9 $ 207.6 $ 44.8 $ 364.3 Accumulated impairment losses — — — — Net book amount $ 111.9 $ 207.6 $ 44.8 $ 364.3 Exchange effect (5.4 ) (0.1 ) — (5.5 ) At December 31, 2022 Gross cost $ 106.5 $ 207.5 $ 44.8 $ 358.8 Accumulated impairment losses — — — — Net book amount $ 106.5 $ 207.5 $ 44.8 $ 358.8 The Company’s reporting units, the level at which goodwill is tested for impairment, are consistent with the reportable segments: Performance Chemicals, Fuel Specialties and Oilfield Services. The components in each segment (including products, markets and competitors) have similar economic characteristics and the segments, therefore, reflect the lowest level at which operations and cash flows can be clearly distinguished, operationally and for financial reporting purposes, from the rest of the Company. The Company assesses goodwill for impairment on at least an annual basis, initially based on a qualitative assessment to determine whether it is more likely than not that the fair value of a segment is less than the carrying amount. If a potential impairment is identified then an impairment test is performed. The Company performed its annual impairment assessment in respect of goodwill as at December 31, 2022, 2021 and 2020. Our impairment assessment concluded that there had been no impairment of goodwill in respect of those reporting units. We believe that where appropriate the assumptions used in our impairment assessments are reasonable, but that they are judgmental, and variations in any of the assumptions may result in materially different calculations of any potential impairment charges.

Other Intangible Assets

Other Intangible Assets	12 Months Ended
	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Other Intangible Assets	Note 9. Other Intangible Assets The following table analyzes other intangible assets movement for 2022 and 2021. (in millions) 2022 2021 Gross cost at January 1 $ 295.2 $ 298.9 Additions 2.7 0.0 Written down in the year (4.1 ) 0.0 Exchange effect (2.7 ) (3.7 ) Gross cost at December 31 291.1 295.2 Accumulated amortization at January 1 (237.7 ) (223.6 ) Amortization expense (14.0 ) (16.0 ) Written down in the year 4.1 0.0 Exchange effect 1.5 1.9 Accumulated amortization at December 31 (246.1 ) (237.7 ) Net book amount at December 31 $ 45.0 $ 57.5 Amortization expense The amortization expense was $14.0 million, $16.0 million and $20.9 million in 2022, 2021 and 2020, respectively. Excluding the impact of foreign exchange translation on the balance sheet, $2.3 million, $2.3 million and $2.9 million of amortization, respectively, was recognized in cost of goods sold, and the remainder was recognized in selling, general and administrative expenses. In 20 2 million in relation to our internally developed software for a new Enterprise Resource Planning (“ERP”) system covering our EMEA and ASPAC regions. The expenses capitalized include the acquisition costs for the software as well as the external and internal costs of the development. We are expecting to complete the project in the first half of 2024 with the additional completion costs currently planned to be approximately Other intangible assets at December 31, 2022 were: (in millions) Gross Accumulated Product rights $ 34.0 $ (34.0 ) Brand names 8.9 (7.8 ) Technology 55.1 (40.0 ) Customer relationships 122.9 (96.9 ) Internally developed software 45.2 (42.4 ) Other 25.0 (25.0 ) $ 291.1 $ (246.1 ) Other intangible assets at December 31, 2021 were: (in millions) Gross Accumulated Product rights $ 34.0 $ (31.5 ) Brand names 8.9 (7.2 ) Technology 55.1 (37.7 ) Customer relationships 125.3 (90.7 ) Internally developed software 43.1 (41.8 ) Other 28.8 (28.8 ) $ 295.2 $ (237.7 ) Future amortization expense is estimated to be as follows for the next five years: (in millions) 2023 $ 10.6 2024 $ 9.9 2025 $ 6.9 2026 $ 6.8 2027 $ 3.3

Pension and Post-Employment Ben

Pension and Post-Employment Benefits	12 Months Ended
	Dec. 31, 2022
Retirement Benefits [Abstract]
Pension and Post-Employment Benefits	Note 10. Pension and Post-Employment Benefits United Kingdom plan The Company maintains a defined benefit pension plan covering certain current and former employees in the United Kingdom (the “UK Plan”). The UK Plan is closed to future service accrual and has a large number of deferred and current pensioners. The Projected Benefit Obligation (“PBO”) is based on final salary and years of credited service reduced by social security benefits according to a plan formula. Normal retirement age is 65 but provisions are made for early retirement. In May 2022, the Trustees of the UK Plan entered into an agreement with Legal and General Assurance Society Limited to acquire an insurance policy that operates as an investment asset, with the intent of matching the remaining uninsured part of the UK Plan’s future cash outflow arising from the accrued pension liabilities of members. Such an arrangement is commonly termed as a “buy-in”. buy-in improving the security to the UK Plan and its members. The Company consequently benefits from the buy-in In 2022, the Company contributed $0.0 million (2021 – $0.0 million) in cash to the UK Plan in accordance w ith a there The service cost shown in the table below has been recognized in sel ling, gen and admi corporate (in millions) 2022 2021 2020 Service cost $ 2.2 $ 1.6 $ 1.2 Interest cost on PBO 10.1 7.6 11.2 Expected return on plan assets (16.0 ) (15.5 ) (17.8 ) Amortization of prior service cost/(credit) 0.5 0.3 (0.5 ) Amortization of actuarial net losses — 1.6 0.9 Settlement event — (0.3 ) — Net periodic benefit $ (3.2 ) $ (4.7 ) $ (5.0 ) Plan assumptions at December 31, (%): 20 22 2021 2020 Discount rate 4.91 1.84 1.36 Inflation rate 2.85 3.55 2.35 Rate of return on plan assets – overall on bid-value 4.00 2.30 2.00 Plan asset allocation by category (%): 2022 2021 2020 Debt securities and insurance contracts 96 82 86 Equity securities and real estate — 5 10 Cash 4 13 4 100 100 100 Following the buy-in, The inflation rate is derived using a similar cash flow matched methodology as used for the discount rate but having regard to the difference between yields on fixed interest and index linked United Kingdom government gilts. A % change in the discount rate assumption would change the PBO at December 31, 2022 by approximately $ million and the net pension credit for 2023 would change by approximately $ million. A % change in the level of price inflation assumption would change the PBO at December 31, 2022 by approximately $ million and the net pension credit for 2022 by approximately $ million. Movements in PBO and fair value of UK Plan assets are as follows: (in millions) 2022 2021 Change in PBO: Opening balance $ 679.1 $ 758.7 Interest cost 10.1 7.6 Service cost 2.2 1.6 Benefits paid (45.6 ) (37.3 ) Settlements — (10.6 ) Plan amendments 0.4 5.4 Actuarial losses/(gains) (174.2 ) (40.5 ) Exchange effect (68.0 ) (5.8 ) Closing balance $ 404.0 $ 679.1 Fair value of plan assets: Opening balance $ 838.9 $ 876.7 Benefits paid (45.6 ) (37.3 ) Settlements — (10.6 ) Actual return on assets (258.7 ) 17.5 Exchange effect (82.5 ) (7.4 ) Closing balance $ 452.1 $ 838.9 Net pension asset $ 48.1 $ 159.8 Due to the UK Plan being closed to future accrual the PBO is equal to the Accumulated Benefit Obligation. The UK Plan holds approximately % (December 31, 2021 – %) of the UK non-U . . governments and government agencies. No more than % of the UK Settlement The 2021 settlement threshold for the total of interest cost and service cost was triggered in October 2021 by the level of transfers paid out of the UK Plan during the year. As a result, a settlement value of $10.6 million has been included for the PBO movements in 2021. Debt securities In the prior year, fixed income securities are valued based on quotations received from independent pricing services or from dealers who make markets in such securities and are classified as Level 1. Corporate debt securities are classified as Level 2 in line with the industry standard. Equity backed securities In the prior year, common and preferred stock for which market prices are readily available at the measurement date are valued at the last reported sale price or official closing price on the primary market or exchange on which they are actively traded. Other financial derivatives are classified as Level 2 and certain investments that are measured at fair value using the net asset value per share (or its equivalent) have not been categorized with a hierarchy. Other asset backed securities The Company has invested in insurance contracts, known as buy-in The fair values of pension assets by level of input were as follows: (in millions) Quoted Prices Significant (Level 2) Significant (Level 3) Total At December 31, 2022 Debt securities: Debt securities issued by non-U.S. $ 4.3 $ $ $ 4.3 Corporate debt securities — Equity backed securities: Other financial derivatives — Other asset backed securities: Insurance contracts 431.8 431.8 Real estate Total assets at fair value 4.3 — 431.8 436.1 Cash 16.0 16.0 Total plan assets $ 20.3 $ — $ 431.8 $ 452.1 (in millions) Quoted Prices Significant (Level 2) Significant (Level 3) Total At December 31, 2021 Debt securities: Debt securities issued by non-U.S. $ 80.3 $ $ $ 80.3 Corporate debt securities 445.7 445.7 Equity backed securities: Other financial derivatives (1.5 ) (1.5 ) Other asset backed securities: Insurance contracts 162.2 162.2 Real estate 47.0 47.0 Total assets at fair value 127.3 444.2 162.2 733.7 Cash 105.2 105.2 Total plan assets $ 232.5 $ 444.2 $ 162.2 $ 838.9 (1) Certain investments that are measured at fair value using the net asset value per share (or its equivalent) have not been categorized in the fair value table with a hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statement of financial position. The reconciliation of the fair value of the UK (in millions) Other Assets Balance at December 31, 2020 $ 167.4 Realized/unrealized gains/(losses): Relating to assets still held at the reporting date 3.3 Purchases, issuances and settlements (7.0 ) Exchange effect (1.5 ) Balance at December 31, 2021 $ 162.2 Realized/unrealized gains/(losses): Relating to assets still held at the reporting date (206.6 ) Purchases, issuances and settlements 502.8 Exchange effect (26.6 ) Balance at December 31, 2022 $ 431.8 The projected net periodic benefit for the year ending December 31, 2023 is as follows: (in millions) Service cost $ 3.4 Interest cost on PBO 19.1 Expected return on plan assets (24.5 ) Amortization of prior service credit 0.5 Amortization of actuarial net losses (1.6 ) Net periodic benefit $ (3.1 ) The following benefit payments are expected to be made: (in millions) 2023 $ 33.5 2024 $ 33.4 2025 $ 33.3 2026 $ 32.8 2027 $ 32.6 2028-2032 $ 157.2 German plan The Company also maintains an unfunded defined benefit pension plan covering certain current and former employees in Germany (the “German plan”), which is reported within our Fuel Specialties segment. The German plan is closed to new entrants and has no assets. The service cost shown in the table below has been recognized in selling, general and administrative expenses within corporate costs and the other items recognized within other income, net. (in millions) 2022 2021 2020 Service cost $ 0.1 $ 0.1 $ 0.1 Interest cost on PBO 0.1 0.1 0.1 Amortization of actuarial net loss 0.5 1.0 0.8 Net periodic cost $ 0.7 $ 1.2 $ 1.0 Plan assumptions at December 31, (%): Discount rate 3.70 0.90 0.40 Inflation rate 2.25 2.00 1.50 Rate of increase in compensation levels 2.75 2.75 2.75 Movements in PBO of the German plan are as follows: (in millions) 2022 2021 Change in PBO: Opening balance $ 13.2 $ 15.2 Service cost 0.1 0.1 Interest cost 0.1 0.1 Benefits paid (0.3 ) (0.4 ) Actuarial losses/(gains) (4.0 ) (0.7 ) Exchange effect (0.9 ) (1.1 ) Closing balance $ 8.2 $ 13.2 Other plans As at December 31, 2022, we have post-employment obligations in our Performance Chemicals European businesses with a liability of $4.1 million (December 31, 2021 – $4.6 million). For the year ended December 31, 2022 we have recognized an actuarial gain of $0.3 million in other comprehensive loss in relation to the Performance Chemicals pension in France (December 31, 2021 – $0.1 million). Company contributions to defined contribution schemes during 2022 were $11.0 million (2021 – $10.9 million), across all our reporting segments.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	Note 11. Income Taxes A roll-forward of unrecognized tax benefits and associated accrued interest and penalties is as follows: (in millions) Unrecognised Tax Benefits Interest Total Opening balance at January 1, 2020 $ 14.4 $ 2.0 $ 16.4 Reductions for tax positions of prior periods (1.2 ) (0.2 ) (1.4 ) Additions for tax positions of prior periods 0.4 0.6 1.0 Closing balance at 31 December, 2020 13.6 2.4 16.0 Current — — — Non-current $ 13.6 $ 2.4 $ 16.0 Opening balance at January 1, 2021 $ 13.6 $ 2.4 $ 16.0 Reductions for tax positions of prior periods (1.3 ) 0.0 (1.3 ) Additions for tax positions of prior periods 0.9 0.7 1.6 Closing balance at 31 December, 2021 13.2 3.1 16.3 Current — — — Non-current $ 13.2 $ 3.1 $ 16.3 Opening balance at January 1, 2022 $ 13.2 $ 3.1 $ 16.3 Reductions for tax positions of prior periods (3.1 ) — (3.1 ) Additions for tax positions of prior periods 0.1 0.1 0.2 Closing balance at 31 December, 2022 10.2 3.2 13.4 Current — — — Non-current $ 10.2 $ 3.2 $ 13.4 All of the $13.4 million of unrecognized tax benefits would impact our effective tax rate if recognized. In 2021 a non-U.S. A non-U.S. $0.2 million foreign exchange movements recorded during 2022. 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, an indemnification asset of the same amount is recorded in the financial statements to reflect this arrangement. In 2018 the Company recorded an unrecognized tax benefit in relation to a potential adjustment that could arise as a consequence of the Tax Cuts and Jobs Act of 2017 (“Tax Act”), but The Company and its U.S. subsidiaries remain open to examination by the IRS for certain elements of 2017 year and for years 2019 onwards under the statute of limitations. The Company’s subsidiaries in foreign tax jurisdictions are open to examination including Brazil (2018 onwards), Germany (2018 onwards), and the U.K. (2017 onwards). The sources of income before income taxes were as follows: (in millions) 2022 2021 2020 Domestic $ 106.3 $ 53.2 $ (0.7 ) Foreign 78.3 81.2 40.4 $ 184.6 $ 134.4 $ 39.7 The components of income tax expense are summarized as follows: (in millions) 2022 2021 2020 Current: Federal $ 27.0 $ 12.4 $ 6.1 State and local 6.5 2.6 0.5 Foreign 23.1 19.4 6.8 56.6 34.4 13.4 Deferred: Federal (3.7 ) (1.9 ) (2.8 ) State and local (0.7 ) (0.3 ) (0.4 ) Foreign (0.6 ) 9.1 0.8 (5.0 ) 6.9 (2.4 ) $ 51.6 $ 41.3 $ 11.0 Cash payments for income taxes were $50.0 million, $36.8 million and $23.4 million during 2022, 2021 and 2020, respectively. The effective tax rate varies from the U.S. federal statutory rate because of the factors indicated below: (in percent) 2022 2021 2020 Statutory rate 21.0 % 21.0 % 21.0 % Foreign income inclusions 3.3 1.7 7.1 Foreign tax rate differential 0.9 1.0 4.2 Tax charge/(credit) from previous years 0.2 0.6 3.7 Net charge/(credit) from unrecognized tax benefits (1.4 ) 0.4 (1.7 ) Foreign currency transactions 3.5 0.1 (4.5 ) Tax on unremitted earnings 0.3 0.1 0.3 Non-deductible — — 0.7 Change in U.K. statutory tax rate — 5.4 6.9 State and local taxes 2.2 1.3 1.5 U.S. incentive for foreign derived intangible income (2.7 ) (1.5 ) (1.5 ) Innovation incentives – current year (0.8 ) (1.1 ) (4.9 ) Innovation incentives – prior years — — (5.3 ) Non-deductible 1.4 0.2 1.8 Tax on closure of legacy operations — 1.6 — Other items and adjustments, net 0.1 (0.1 ) (1.6 ) 28.0 % 30.7 % 27.7 % Foreign income inclusions arise each year from certain types of income earned overseas being taxable under U.S. tax regulations. Foreign tax credits can fully or partially offset these incremental U.S. taxes from foreign income inclusions. The utilization of foreign tax credits varies year on year as this is dependent on a number of variable factors which are difficult to predict and may prevent offset. The effective tax rate is negatively impacted by the net impact of foreign inclusions post foreign tax credit usage in 2022. As a consequence of the Company having operations outside of the U.S., it is exposed to foreign currency fluctuations. These have had a negative impact on the effective tax rate in 2022. In 2022 there was an increase in the level of profits arising in the U.S. compared to prior periods. This has increased the amount of state and local taxes falling due, which has had a negative impact on the effective tax rate, but has also increased the level of foreign-derived intangible income benefit that the Company is entitled to, which has had a positive impact on the effective tax rate in the year. Other items do not have a significant impact on the effective tax rate. Details of deferred tax assets and liabilities are analyzed as follows: (in millions) 2022 2021 Deferred tax assets: Stock compensation $ 3.7 $ 5.2 Net operating loss carry forwards 10.9 12.0 Other intangible assets 10.5 11.1 Accretion expense 3.2 3.2 Restructuring provision 1.7 2.0 Employee related liabilities 8.1 4.1 Foreign tax credits 0.8 1.9 Operating lease liabilities 11.8 10.6 Inventory provisions 6.6 3.6 Research and experimental expenditure 2.7 — Other 4.8 3.8 Subtotal 64.8 57.5 Less valuation allowance (0.7 ) (0.8 ) Total net deferred tax assets $ 64.1 $ 56.7 Deferred tax liabilities: Property, plant and equipment $ (22.5 ) $ (23.6 ) Intangible assets including goodwill (30.3 ) (29.8 ) Pension asset (10.9 ) (38.2 ) Customer relationships (3.4 ) (4.5 ) Unremitted overseas earnings (1.9 ) (1.9 ) Right-of-use (11.8 ) (10.6 ) Other (3.6 ) (2.5 ) Total deferred tax liabilities $ (84.4 ) $ (111.1 ) Net deferred tax liability $ (20.3 ) $ (54.4 ) Deferred tax assets $ 5.9 $ 6.4 Deferred tax liabilities (26.2 ) (60.8 ) $ (20.3 ) $ (54.4 ) The Company assesses the available positive and negative evidence to estimate whether sufficient future taxable income will be generated to permit use of the existing deferred tax assets. Available evidence considered in determining the use of deferred tax assets includes, but is not limited to, cumulative losses arising in recent accounting periods, the Company’s estimate of future taxable income and any applicable tax-planning $0.7 million has been recorded to recognize As of December 31, 2022, the Company has approximately $5.1 million of tax-effected tax-effected s

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2022
Debt Disclosure [Abstract]
Long-Term Debt	Note 12. Long-Term Debt As at December 31, 2022, and December 31, 2021, the Company has not drawn down on its revolving credit facility. The Company continues to have available a $250.0 million revolving credit facility until September 25, 2024. The facility contains an accordion feature whereby the Company may elect to increase the total available borrowings by an aggregate amount of up to $125.0 million. The deferred finance costs of $0.6 million (December 31, 2021 – $1.0 million) related to the arrangement of the credit facility, are included within other current and non-current (in millions) 2022 2021 Gross cost at January 1 $ 1.8 $ 1.8 Capitalized in the year — — 1.8 1.8 Accumulated amortization at January 1 $ (0.8 ) $ (0.5 ) Amortization in the year (0.4 ) (0.3 ) $ (1.2 ) $ (0.8 ) Net book value at December 31 $ 0.6 $ 1.0 Amortization expense was $0.4 million, $0.3 million and $0.4 million in 2022, 2021 and 2020, respectively. The charge is included in interest expense, see Note 2 of the Notes to the Consolidated Financial Statements. The obligations of the Company under the credit facility are secured obligations and guaranteed by certain subsidiaries of the Company. Amounts available under the revolving facility may be borrowed in U.S. dollars, Euros, British pounds and other freely convertible currencies. The Company’s credit facility contains restrictive clauses which may constrain our activities and limit our operational and financial flexibility. The facility obliges the lenders to comply with a request for utilization of finance unless there is an event of default outstanding. Events of default are defined in the credit facility and include a material adverse change to our assets, operations or financial condition. The facility contains a number of restrictions that limit our ability, amongst other things, and subject to certain limited exceptions, to incur additional indebtedness, pledge our assets as security, guarantee obligations of third parties, make investments, undergo a merger or consolidation, dispose of assets, or materially change our line of business. In addition, the credit facility contains terms which, if breached, would result in it becoming repayable on demand. It requires, among other matters, compliance with the following financial covenant ratios measured on a quarterly basis: (1) the ratio of net debt to EBITDA shall not be greater than 3.0:1 and (2) the ratio of EBITDA to net interest shall not be less than 4.0:1. Management has determined that the Company has not breached these covenants throughout the period to December 31, 2022 and does not expect to breach these covenants for the next 12 months. The weighted average rate of interest on borrowings was 0.00% at December 31, 2022 and 0.00% at December 31, 2021. Payments of interest on long-term debt were $0.0 million, $0.0 million and $0.8 million in 2022, 2021 and 2020, respectively. The net cash outflows in respect of refinancing costs were $0.0 million, $0.0 million and $0.3 million in 2022, 2021 and 2020, respectively.

Plant Closure Provisions

Plant Closure Provisions	12 Months Ended
	Dec. 31, 2022
Restructuring and Related Activities [Abstract]
Plant Closure Provisions	Note 13. Plant Closure Provisions The Company has continuing plans to remediate manufacturing facilities at sites around the world as and when those operations are expected to cease or we are required to decommission the sites according to local laws and regulations. The liability for estimated plant closure costs includes costs for environmental remediation liabilities and asset retirement obligations. The principal site giving rise to asset retirement obligations is the manufacturing site at Ellesmere Port in the United Kingdom. There are also asset retirement obligations and environmental remediation liabilities on a much smaller scale in respect of other manufacturing sites. Movements in the provisions are summarized as follows: (in millions) 2022 2021 2020 Total at January 1 $ 56.5 $ 58.5 $ 49.3 Charge for the period excluding restructuring 5.3 3.9 5.1 Restructuring (see Note 5) — — 7.5 Utilized in the period (4.2 ) (5.3 ) (4.1 ) Exchange effect (0.4 ) (0.6 ) 0.7 Total at December 31 57.2 56.5 58.5 Due within one year (5.3 ) (5.2 ) (6.6 ) Due after one year $ 51.9 $ 51.3 $ 51.9 Amounts due within one year refer to provisions where expenditure is expected to arise within one year of the balance sheet date. The charge for the period in 2022 represents the accretion expense recognized of $3.8 million and a further $1.5 million primarily in respect of changes in the expected cost and scope of future remediation activities. The charges for plant closure provisions are recognized in cost of goods sold for our reporting segments and within selling, general and administrative expenses for Corporate costs. The Octane Additives segment ceased trading and is no longer a reporting segment from July 1, 2020. As a result, there was a one-off We recognize environmental remediation liabilities when they are probable and the costs can be reasonably estimated, and asset retirement obligations when there is an obligation based on a legal requirement, including those arising from a Company promise, and the costs can be reasonably estimated. The Company has to anticipate the program of work required and the associated future expected costs, and comply with environmental legislation in the countries in which it operates or has operated in. Expenditure utilizing plant closure provisions was $4.2 million, $5.3 million and $4.1 million in 2022, 2021 and 2020, respectively.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 14. Fair Value Measurements Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). The Company utilizes a mid-market inputs can be readily observable, market corroborated or generally unobservable. The Company primarily applies the market approach for recurring fair value measurements and endeavors to utilize the best available information. Accordingly, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. The Company is able to classify fair value balances based on the observability of those inputs. The Company gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy Levels. In 2019, the Company evaluated the fair value hierarchy levels assigned to its assets and liabilities, and concluded that there should be no transfers into or out of Levels 1, 2 and 3. The following table presents the carrying amount and fair values of the Company’s assets and liabilities measured on a recurring basis: December 31, 2022 December 31, 2021 (in millions) Carrying Amount Fair Value Carrying Amount Fair Value Assets Non-derivatives: Cash and cash equivalents $ 147.1 $ 147.1 $ 141.8 $ 141.8 Derivatives (Level 1 measurement): Other current and non-current Emissions Trading Scheme credits 2.7 2.7 3.9 3.9 Liabilities Non-derivatives: Finance leases (including current portion) $ — $ — $ 0.1 $ 0.1 Derivatives (Level 1 measurement): Other current liabilities: Foreign currency forward exchange contracts 0.5 0.5 1.2 1.2 Non-financial Stock equivalent units 26.4 26.4 17.3 17.3 The following methods and assumptions were used to estimate the fair values: Cash and cash equivalents: Emissions Trading Scheme credits: Long-term debt: Derivatives: Stock equivalent units:

Derivative Instruments and Risk

Derivative Instruments and Risk Management	12 Months Ended
	Dec. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Risk Management	Note 15. Derivative Instruments and Risk Management The Company has limited involvement with derivative instruments and does not trade them. The Company does use derivatives to manage certain interest rate, foreign currency exchange rate, raw material cost exposures and greenhouse gases emission allowances, as the need arises. The Company previously entered into interest rate swap contracts to reduce interest rate risk on its core debt. As at December 31, 2022 and at December 31, 2021, there were no interest rate swaps in place. Interest rate swaps were previously in place to hedge interest rate risk on the term loan for a notional value that matched the repayment profile of the term loan. The Company enters into various foreign currency forward exchange contracts to minimize currency exchange rate exposure from expected future cash flows. As at December 31, 2022, foreign currency forward exchange contracts with a notional value of $161.1 million were in place (December 31, 2021 $113.0 million), with maturity dates of up to one year from 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 2022 was a gain of $0.7 million (2021 – gain $1.0 million). As at December 31, 2022 and December 31, 2021 the Company did not hold any raw material derivatives. The Company participates in the new United Kingdom Emissions Trading Scheme (“UK ETS”) which was launched on January 1, 2021. Emissions trading schemes work on the ‘cap and trade’ principle, where a cap is set on the total amount of certain greenhouse gases that can be emitted by sectors covered by the scheme. This limits the total amount of carbon that can be emitted. Within this cap, participants receive free allowances and/or buy emission allowances at auction or on the secondary market which they can trade with other participants as needed. As at December 31, 2022, the Company held UK ETS credits of $2.7 million (December 31, 2021 – $3.9 million). The Company sells a range of specialty chemicals to major oil refiners and chemical companies throughout the world. Credit limits, ongoing credit evaluation and account monitoring procedures are intended to minimize bad debt risk. Collateral is not generally required.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 16. Commitments and Contingencies Environmental remediation liabilities and asset retirement obligations Commitments in respect of environmental remediation liabilities and asset retirement obligations are disclosed in Note 13 of the Notes to the Consolidated Financial Statements. Capital commitments The estimated additional cost to complete work in progress at December 31, 2022 is $37.7 million (2021 – $23.5 million). Internally developed software The estimated additional cost to complete work in progress at December 31, 2022 is $25.0 million (2021 – $0.0 million). 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 items could in the aggregate have a material adverse effect on 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 non-U.S. Under 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.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2022
Equity [Abstract]
Stockholders' Equity	Note 17. Stockholders’ Equity Common Stock Treasury Stock (number of shares in thousands) 2022 2021 2020 2022 2021 2020 At January 1 29,554.5 29,554.5 29,554.5 4,781 4,959 5,047 Exercise of options — — — (55 ) (185 ) (109 ) Stock purchases — — — 63 7 21 At December 31 29,554.5 29,554.5 29,554.5 4,789 4,781 4,959 At December 31, 2022, the Company had authorized common stock of 40,000,000 shares (2021 - 40,000,000).

Share-Based Compensation Plans

Share-Based Compensation Plans	12 Months Ended
	Dec. 31, 2022
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation Plans	Note 18. Share-Based Compensation Plans Stock option plans The Company has two stock option plans, the Omnibus Long-Term Incentive Plan and the ShareSave Plan 2008 under which it currently grants awards. The stock options have vesting periods ranging from 2 to 5 years and in all cases stock options granted expire within 10 years of the date of grant. All grants are at the sole discretion of the Compensation Committee of the Board of Directors. Grants may be priced at market value or at a premium or discount. The aggregate number of shares of common stock reserved for issuance which can be granted under the plans is 2,550,000. In the fourth quarter of 2020, a number of stock options that were granted to 14 employees in February 2018 were modified to extend the vesting period by two years. The incremental compensation cost resulting from the modifications was $2.4 million, resulting from the performance targets that were not achieved in 2020 being extended to a future period. The fair value of stock options is measured on the grant date using either the Black-Scholes model, or in cases where performance criteria are dependent upon external factors such as the Company’s stock price, using a Monte Carlo model. The Company’s policy is to issue shares from treasury stock to holders of stock options who exercise those options, but if sufficient treasury stock is not available, the Company will issue previously unissued shares of stock to holders of stock options who exercise options. Stock equivalent units The Company awards Stock Equivalent Units (“SEUs”) from time to time as a long-term performance incentive. SEUs are cash settled equity instruments conditional on certain performance criteria and the fair value is linked to the Innospec Inc. share price. SEUs have vesting periods ranging from six months to 5 years and in all cases SEUs granted expire within 10 years of the date of grant. Grants may be priced at market value or at a premium or discount. There is no limit to the number of SEUs that can be granted. As at December 31, 2022 the liability for SEUs of $26.4 million is included in accrued liabilities in the consolidated balance sheet, where they will remain In the fourth quarter of 2020, a number of SEUs that were granted to 61 employees in February 2018 were modified to extend the vesting period by two years. The adjusted compensation cost resulting from the modifications has been recognised by the fair valuation at the balance sheet date based on the extended vesting period. The fair value of SEUs is re-measured Compensation cost The compensation cost recorded for stock options was $6.7 million, $4.4 million and $5.8 million for 2022, 2021 and 2020, respectively. The compensation cost for stock options is based on the grant-date fair value and spread evenly over the vesting period. The compensation cost recorded for SEUs was $24.2 million, $3.1 million and $1.9 million for 2022, 2021 and 2020, respectively. The compensation cost for SEUs is spread over the life of the award subject to a revaluation to the fair value at each quarter end. The revaluation may result in a charge or a credit to the income statement in each quarter dependent upon our share price movements and other performance criteria. Forfeits are accounted for as an adjustment to the charge in the period in which the forfeits occur. Transactions in the period The fair value of each stock option or SEU granted in the year was estimated on the date of grant using the Black-Scholes option-pricing model and where appropriate the Monte Carlo simulation model. These models utilized the following weighted average assumptions to determine the grant-date fair values of the share-based compensation granted in the year: 2022 2021 2020 Dividend yield 1.27 % 1.17 % 1.15 % Expected life 5 years 5 years 5 years Volatility 39.8 % 40.2 % 27.4 % Risk free interest rate 2.90 % 0.45 % 1.10 % The dividend yield was based on our recent history of dividend payouts. The expected life was determined based upon historical exercise experience. The volatility was determined based upon the historical The following tables summarizes the transactions of the Company’s share-based compensation plans for the year ended December 31, 2022. Number of Weighted Average Grant-Date Fair Value Nonvested at December 31, 2021 680,711 $ 74.6 Granted 332,009 $ 60.2 Vested (178,886 ) $ 72.7 Forfeited (76,794 ) $ 71.2 Nonvested at December 31, 2022 757,040 $ 69.0 Number of Weighted Average Exercise price Outstanding at December 31, 2021 813,971 $ 8.0 Granted 332,009 $ 40.9 Exercised (203,788 ) $ 12.4 Forfeited (77,674 ) $ 2.1 Outstanding at December 31, 2022 864,518 $ 20.1 Exercisable at December 31, 2022 107,478 $ 12.6 Other disclosures As at December 31, 2022, there was $ 23.1 million of total unrecognized compensation cost related to nonvested share-based compensation arrangements. That cost is expected to be recognized over a weighted-average period of 1.9 years. The total intrinsic value of share-based compensation plans outstanding at December 31, 2022 was $71.5 million. The total intrinsic value of share-based compensation plans exercisable at December 31, 2022 was $9.7 million. The total intrinsic value of share-based compensation plans exercised for the year ended December 31, 2022 was approximately $18.1 million. The total cash paid for SEUs exercised for the year ended December 31, 2022 was approximately $15.0 million. The total fair value of share-based compensation that vested for the year ended December 31, 2022 was $13.0 million. The weighted-average grant-date fair value of share-based compensation plans granted during 2022, 2021, and 2020 was $60.2, $84.8, and $72.4, respectively. The Company recorded a current tax charge of $0.7 million in 2022, and a current tax benefit of $1.3 million and $1.6 million in 2021 and 2020, respectively, in relation to stock option compensation. This amount is inclusive of excess tax benefits.

Reclassifications out of Accumu

Reclassifications out of Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2022
Equity [Abstract]
Reclassifications out of Accumulated Other Comprehensive Loss	Note 19. Reclassifications out of Accumulated Other Comprehensive Loss Reclassifications out of accumulated other comprehensive loss (“AOCL”) for 2022 were: (in millions) Amount Affected Line Item in the Details about AOCL Components Defined benefit pension plan items: Amortization of prior service cost $ 0.5 See (1) below Amortization of actuarial net losses 0.5 See (1) below 1.0 Total before tax (0.2 ) Income tax expense Total reclassifications $ 0.8 Net of tax (1) These items are included in the computation of net periodic pension cost. See Note 10 of the Notes to the Consolidated Financial Statements for additional information. Changes in AOCL for 2022, net of tax, were: (in millions) Defined Cumulative Total Balance at December 31, 2021 $ 10.7 $ (57.6 ) $ (46.9 ) Other comprehensive income/(losses) before reclassifications — (29.2 ) (29.2 ) Amounts reclassified from AOCL 0.8 — 0.8 Actuarial net gains/(losses) arising during the year (69.9 ) — (69.9 ) Net current period other comprehensive income/(losses) (69.1 ) (29.2 ) (98.3 ) Balance at December 31, 2022 $ (58.4 ) $ (86.8 ) $ (145.2 ) Reclassifications out of AOCL for 2021 were: (in millions) Amount Reclassified from AOCL Affected Line Item in the Statement where Details about AOCL Components Defined benefit pension plan items: Amortization of prior service cost $ 0.3 See (1) below Amortization of actuarial net losses 2.6 See (1) below 2.9 Total before tax (0.5 ) Income tax expense Total reclassifications $ 2.4 Net of tax (1) These items are included in the computation of net periodic pension cost. See Note 10 of the Notes to the Consolidated Financial Statements for additional information. Changes in AOCL for 2021, net of tax, were: (in millions) Defined Cumulative Total Balance at December 31, 2020 $ (19.9 ) $ (37.4 ) $ (57.3 ) Other comprehensive income/(losses) before reclassifications — (20.2 ) (20.2 ) Amounts reclassified from AOCL 2.4 — 2.4 Actuarial net gains arising during the year 28.2 — 28.2 Net current period other comprehensive income/(losses) 30.6 (20.2 ) 10.4 Balance at December 31, 2021 $ 10.7 $ (57.6 ) $ (46.9 )

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	12 Months Ended
	Dec. 31, 2022
Accounting Changes and Error Corrections [Abstract]
Recently Issued Accounting Pronouncements	Note 20. Recently Issued Accounting Pronouncements In December 2019, the Financial Accounting Standards Board issued Accounting Standards Update (ASU) No. 2019-12, In March 2020, the Financial Accounting Standards Board issued Accounting Standards Update (“ASU”) No. 2020-04, 1-, 3-, 6-, 12-month No. 2022-06,

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2022
Related Party Transactions [Abstract]
Related Party Transactions	Note 21. Related Party Transactions Mr. Patrick S. Williams has been an executive director of the Company since April 2009 and has been a non-executive Mr. Robert I. Paller has been a non-executive Mr. David F. Landless has been a non-executive non-executive of $0.1 million (2021 – $0.6 million; 2020 – $0.2 million). A tendering process is operated periodically

Accounting Policies (Policies)

Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Basis of preparation	Basis of preparation:
Use of estimates	Use of estimates:
Revenue recognition	Revenue recognition: on-demand While some of our customers have payment terms beyond 30 days, we do not provide extended payment terms of a year or more, nor do our contracts include a financing component. Some of our contracts include variable consideration in the form of rebates. We record rebates at the point of sale as a reduction in sales when we can reasonably estimate the amount of the rebate. The estimates are based on our best judgment at the time of sale, which includes anticipated as well as historical performance. Taxes assessed by a governmental authority which are concurrent with sales to our customers, including sales, use, value-added, and revenue-related excise taxes, are collected by us from the customer and are not included in net sales, but are reflected in accrued liabilities until remitted to the appropriate governmental authority. When we are responsible for shipping and handling costs after title has transferred, we account for those as fulfilment costs and include them in cost of goods sold.
Components of net sales	Components of net sales:
Components of cost of goods sold	Components of cost of goods sold: non-recoverable
Components of selling, general and administrative expenses	Components of selling, general and administrative expenses:
Research and development expenses	Research and development expenses:
Earnings per share	Earnings per share:
Foreign currencies	Foreign currencies: where the U.S. dollar is the functional currency no gains or losses on translation occur, and gains or losses on monetary assets relating to currencies other than the U.S. dollar are taken to the income statement in other income/(expense), net. Gains and losses on intercompany foreign currency loans which are long-term in nature, which the Company does not intend to settle in the foreseeable future, are also recorded in accumulated other comprehensive loss. Other foreign exchange gains or losses are also included in other income, net in the income statement.
Share-based compensation plans	Share
Business combinations	Business combinations: The determination of the fair values of certain assets and liabilities are usually based on significant estimates provided by management, such as forecast revenue or profit. In determining the fair value of intangible assets, an income approach is generally used and may incorporate the use of a discounted cash flow method. In applying the discounted cash flow method, the estimated future cash flows and residual values for each intangible asset are discounted to a present value using a discount rate appropriate to the business being acquired. These cash flow projections are based on management’s estimates of economic and market conditions including revenue growth rates, operating margins, capital expenditures and working capital requirements.
Cash equivalents	Cash equivalents:
Trade and other accounts receivable	Trade and other accounts receivable: The Company is exposed to credit losses primarily through sales of products. The Company’s expected loss allowance methodology for trade and other accounts receivable is developed using historical collection experience, current and future economic and market conditions and a review of the current status of customers’ receivables. Due to the short-term nature of such receivables, the estimate of accounts receivable amounts that may not be collected is based on aging of the accounts receivable balances and the financial condition of customers. Additionally, a further allowance is included to account for the Company’s historic track record of credit losses, for balances which are not aged sufficiently to be considered under the aging based approach .
Inventories	Inventories:
Property, plant and equipment	Property, plant and equipment: Buildings 7 to 25 years Equipment 3 to 10 years
Goodwill and other intangible assets	Goodwill: Initially we perform a qualitative assessment to determine whether it is more likely than not (that is, a likelihood of more than 50 percent) that the fair value of a reportable segment is less than the carrying amount prior to performing a quantitative goodwill impairment test. The annual measurement date for impairment assessment of the goodwill relating to the Performance Chemicals, Fuel Specialties and Oilfield Services segments is December 31 each year. Factors utilized in the qualitative assessment process include macroeconomic conditions, industry and market considerations, cost factors, overall financial performance and Company specific events. If a quantitative test is required, we assess the fair value based on projected post-tax projected operating margins, changes in working capital and discount rates. We would develop these assumptions by considering recent financial performance and industry growth estimates. O ther intangible assets: . In order to facilitate testing for potential impairment the Company groups together assets at the lowest possible level for which cash flow information is available. Undiscounted future cash flows expected to result from the asset groups are compared with the carrying value of the assets and, if such cash flows are lower, an impairment loss may be recognized. The amount of the impairment loss is the difference between the fair value and the carrying value of the assets. Fair values are determined using post-tax non-cash The estimated useful lives of the major classes of assets are as follows: Technology 10 to 17 years Customer lists 10 to 15 years Brand names 5 to 10 years Product rights 9 to 10 years Internally developed software 3 to 10 years Marketing related 11 years
Leases	Leases: right-of-use non-current) non-current) Operating lease ROU assets and operating lease liabilities are recognized based on the present value of future lease payments over the remaining lease term. Very few of our leases have renewal options or early termination break clauses, but where they do we have assessed the term of the lease based on any options being exercised only if they are reasonably certain. As most of our leases do not provide an implicit interest rate, we use our incremental borrowing rate based on the information available at point of recognition in determining the present value of future payments. The operating lease ROU asset excludes lease incentives and initial direct costs incurred. Lease expense for lease payments is recognized on a straight-line basis over the lease term unless payments are variable per the agreement. We do not separate related non-lease We do not recognize a ROU asset or operating lease liability for short-term leases (with a length of one year or less), and any associated cost is recognized, as incurred, through the income statement .
Deferred finance costs	Deferred finance costs:
Impairment of long-lived assets	Impairment of long-lived assets: post-tax
Derivative instruments	Derivative instruments: From non-current earnings.
Plant closure provisions	Plant closure provisions: This and extend to environmental liabilities that result from other-than-normal operation of long-lived assets, for example pollution. Remediation costs relate to asset retirement obligations at our current and former manufacturing sites following retirement of the long-lived assets, linked to their normal operation. We recognize environmental liabilities when they are probable and the costs can be reasonably estimated, and asset retirement obligations when there is an obligation based on a legal requirement , including those arising from a The Company must comply with environmental legislation in the countries in which it operates or has operated in and annually reassesses the program of work required. This includes estimating the credit-adjusted risk free rate and the timing and cost of performing the remediation work. Management receives input from specialists to develop these estimates and assumptions utilizing the latest information available together with experience of recent costs. While we believe our assumptions for the liabilities are reasonable, they are subjective estimates and it is possible that variations in any of the assumptions will result in materially different calculations to the liabilities we have reported. Costs of future obligations are discounted to their present values using the Company’s credit-adjusted risk-free rate.
Pension plans and other post-employment benefits	Pension plans and other post-employment benefits: year-end. In May 2022, the Trustees of the United Kingdom defined benefit pension plan (“UK Plan”) entered into an agreement with Legal and General Assurance Society Limited to acquire an insurance policy that operates as an investment asset, with the intent of matching the remaining uninsured part of the UK Plan’s future cash outflow arising from the accrued pension liabilities of members. Such an arrangement is commonly termed as a “buy-in”. buy-in buy-in Movements in the Projected Benefit Obligation (“PBO”) are dependent on our assumptions in respect of the discount rate, annual member mortality rates, future return on assets and future inflation.
Income taxes	Income taxes:

Accounting Policies (Tables)

Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Estimated Useful Lives of Major Classes of Depreciable Assets	The estimated useful lives of the major classes of depreciable assets are as follows: Buildings 7 to 25 years Equipment 3 to 10 years
Estimated Useful Lives of Major Classes of Assets	The estimated useful lives of the major classes of assets are as follows: Technology 10 to 17 years Customer lists 10 to 15 years Brand names 5 to 10 years Product rights 9 to 10 years Internally developed software 3 to 10 years Marketing related 11 years

Segment Reporting and Geograp_2

Segment Reporting and Geographical Area Data (Tables)	12 Months Ended
	Dec. 31, 2022
Segment Reporting [Abstract]
Segment Reporting	The Company evaluates the performance of its segments based on operating income. The following table analyzes sales and other financial information by the Company’s reportable segments: (in millions) 2022 2021 2020 Net Sales: Personal Care $ 393.3 $ 296.1 $ 231.4 Home Care 94.2 93.0 87.0 Other 152.2 136.2 107.0 Performance Chemicals 639.7 525.3 425.4 Refinery and Performance 552.6 445.3 372.9 Other 177.6 173.0 139.8 Fuel Specialties 730.2 618.3 512.7 Oilfield Services 593.8 339.8 255.0 $ 1,963.7 $ 1,483.4 $ 1,193.1 Operating income/(expense): Performance Chemicals $ 95.3 $ 70.9 $ 54.8 Fuel Specialties 121.7 104.6 84.5 Oilfield Services 41.7 10.4 (9.5 ) Octane Additives — — (2.8 ) Corporate costs (71.4 ) (55.6 ) (52.2 ) Restructuring charge — — (21.3 ) Impairment of intangible assets — — (19.8 ) Profit on disposal — 1.8 — Total operating income $ 187.3 $ 132.1 $ 33.7 Identifiable assets at year-end: Performance Chemicals $ 610.4 $ 469.5 $ 391.5 Fuel Specialties 500.6 571.3 509.7 Oilfield Services 297.8 230.8 210.8 Corporate 194.9 299.3 285.4 $ 1,603.7 $ 1,570.9 $ 1,397.4
Summary of Segment Depreciation and Amortization	The following tables analyze sales and other financial information by location: (in millions) 2022 2021 2020 Net sales by source: United States & North America $ 1,244.9 $ 821.6 $ 642.4 United Kingdom 932.5 811.9 689.1 Rest of Europe 116.9 115.6 83.4 Rest of World 67.7 66.4 45.6 Sales between areas (398.3 ) (332.1 ) (267.4 ) $ 1,963.7 $ 1,483.4 $ 1,193.1 Income before income taxes: United States & North America $ 109.1 $ 54.6 $ — United Kingdom 42.9 46.1 16.9 Rest of Europe 25.5 26.4 19.7 Rest of World 7.1 7.3 3.1 $ 184.6 $ 134.4 $ 39.7 Long-lived assets at year-end: United States & North America $ 147.0 $ 137.3 $ 141.0 United Kingdom 50.6 55.4 61.3 Rest of Europe 112.4 112.0 123.2 Rest of World 0.2 0.2 0.2 $ 310.2 $ 304.9 $ 325.7 Identifiable assets at year-end: United States & North America $ 570.9 $ 464.9 $ 368.8 United Kingdom 462.3 533.7 455.8 Rest of Europe 164.0 164.7 171.0 Rest of World 47.7 43.3 30.6 Goodwill 358.8 364.3 371.2 $ 1,603.7 $ 1,570.9 $ 1,397.4

Earnings per Share (Tables)

Earnings per Share (Tables)	12 Months Ended
	Dec. 31, 2022
Earnings Per Share [Abstract]
Summary of Earnings Per Share	Diluted earnings per share includes the effect of options that are dilutive and outstanding during the period. Per share amounts are computed as follows: 2022 2021 2020 Numerator (in millions): Net income available to common stockholders $ 133.0 $ 93.1 $ 28.7 Denominator (in thousands): Weighted average common shares outstanding 24,787 24,647 24,563 Dilutive effect of stock options and awards 195 207 216 Denominator for diluted earnings per share 24,982 24,854 24,779 Net income per share, basic: $ 5.37 $ 3.78 $ 1.17 Net income per share, diluted: $ 5.32 $ 3.75 $ 1.16

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Property, plant and equipment consists of the following: (in millions) 2022 2021 Land $ 20.6 $ 20.7 Buildings 68.7 69.5 Equipment 377.5 371.5 Work in progress 45.7 23.7 Total gross cost 512.5 485.4 Less accumulated depreciation and impairment (291.6 ) (271.0 ) Total net book value $ 220.9 $ 214.4

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2022
Leases [Abstract]
Components of Lease Expense	The components of lease expense were as follows: (in millions) Twelve Months Twelve Months 2022 2021 Finance lease cost: Amortization of right-of-use $ — $ 0.5 Interest on lease liabilities — — Total finance lease cost — 0.5 Operating lease cost 15.6 13.8 Short-term lease cost 7.2 3.8 Variable lease cost 0.3 0.3 Total lease cost $ 23.1 $ 18.4
Supplemental Cash Flow Information Related to Leases	Supplemental cash flow information related to leases is as follows: (in millions) Twelve Months Twelve Months 2022 2021 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 23.1 $ 18.1 Operating cash flows from finance leases 0.1 0.5 Finance cash flows from finance leases — — Right-of-use Operating leases $ 14.9 $ 5.2 Finance leases — —
Supplemental Balance Sheet Information Related to Leases	Supplemental balance sheet information related to leases is as follows: (in millions except lease term and discount rate) December 31 December 31 Operating leases: Operating lease right-of-use $ 45.3 $ 35.4 Current portion of operating lease liabilities $ 13.9 $ 12.4 Operating lease liabilities, net of current portion 31.4 23.1 Total operating lease liabilities $ 45.3 $ 35.5 Finance leases: Property, plant and equipment at cost $ — $ 5.0 Accumulated depreciation — (4.5 ) Net property, plant and equipment $ — $ 0.5 Current portion finance leases $ — $ 0.1 Finance leases, net of current portion — — Total finance lease liabilities $ — $ 0.1 (in millions except lease term and discount rate) December 31 December 31 Weighted average remaining lease term: Operating leases 5.5 years 4.9 years Finance leases — 0.5 years Weighted average discount rate: Operating leases 2.6 % 2.5 % Finance leases — 2.5 %
Maturities of Lease Liabilities	Maturities of lease liabilities were as follows as at December 31, 2022: (in millions) Operating Within one year $ 14.3 Year two 8.9 Year three 6.4 Year four 5.2 Year five 1.5 Thereafter 13.5 Total lease payments 49.8 Less imputed interest (4.5 ) Total $ 45.3 As of December 31, 2022, additional operating and finance leases that have not yet commenced are $2.7 million. Future lease payment for all non-cancellable (in millions) Operating Finance Within one year $ 12.5 $ 0.1 Year two 9.0 — Year three 6.0 — Year four 3.9 — Year five 3.1 — Thereafter 3.2 — Total lease payments 37.7 0.1 Less imputed interest (2.2 ) — Total $ 35.5 $ 0.1

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Goodwill	The following table analyzes goodwill movement for 2022 and 2021. (in millions) Performance Fuel Oilfield Total At December 31, 2020 Gross cost $ 118.5 $ 207.9 $ 44.8 $ 371.2 Accumulated impairment losses — — — — Net book amount $ 118.5 $ 207.9 $ 44.8 $ 371.2 Exchange effect (6.6 ) (0.3 ) — (6.9 ) At December 31, 2021 Gross cost $ 111.9 $ 207.6 $ 44.8 $ 364.3 Accumulated impairment losses — — — — Net book amount $ 111.9 $ 207.6 $ 44.8 $ 364.3 Exchange effect (5.4 ) (0.1 ) — (5.5 ) At December 31, 2022 Gross cost $ 106.5 $ 207.5 $ 44.8 $ 358.8 Accumulated impairment losses — — — — Net book amount $ 106.5 $ 207.5 $ 44.8 $ 358.8

Other Intangible Assets (Tables

Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Other Intangible Assets	The following table analyzes other intangible assets movement for 2022 and 2021. (in millions) 2022 2021 Gross cost at January 1 $ 295.2 $ 298.9 Additions 2.7 0.0 Written down in the year (4.1 ) 0.0 Exchange effect (2.7 ) (3.7 ) Gross cost at December 31 291.1 295.2 Accumulated amortization at January 1 (237.7 ) (223.6 ) Amortization expense (14.0 ) (16.0 ) Written down in the year 4.1 0.0 Exchange effect 1.5 1.9 Accumulated amortization at December 31 (246.1 ) (237.7 ) Net book amount at December 31 $ 45.0 $ 57.5
Schedule of Amortization Expense	Other intangible assets at December 31, 2022 were: (in millions) Gross Accumulated Product rights $ 34.0 $ (34.0 ) Brand names 8.9 (7.8 ) Technology 55.1 (40.0 ) Customer relationships 122.9 (96.9 ) Internally developed software 45.2 (42.4 ) Other 25.0 (25.0 ) $ 291.1 $ (246.1 ) Other intangible assets at December 31, 2021 were: (in millions) Gross Accumulated Product rights $ 34.0 $ (31.5 ) Brand names 8.9 (7.2 ) Technology 55.1 (37.7 ) Customer relationships 125.3 (90.7 ) Internally developed software 43.1 (41.8 ) Other 28.8 (28.8 ) $ 295.2 $ (237.7 ) Future amortization expense is estimated to be as follows for the next five years: (in millions) 2023 $ 10.6 2024 $ 9.9 2025 $ 6.9 2026 $ 6.8 2027 $ 3.3

Pension and Post-Employment B_2

Pension and Post-Employment Benefits (Tables)	12 Months Ended
	Dec. 31, 2022
Plan Net Pension Credit	The service cost shown in the table below has been recognized in sel ling, gen and admi corporate (in millions) 2022 2021 2020 Service cost $ 2.2 $ 1.6 $ 1.2 Interest cost on PBO 10.1 7.6 11.2 Expected return on plan assets (16.0 ) (15.5 ) (17.8 ) Amortization of prior service cost/(credit) 0.5 0.3 (0.5 ) Amortization of actuarial net losses — 1.6 0.9 Settlement event — (0.3 ) — Net periodic benefit $ (3.2 ) $ (4.7 ) $ (5.0 ) Plan assumptions at December 31, (%): 20 22 2021 2020 Discount rate 4.91 1.84 1.36 Inflation rate 2.85 3.55 2.35 Rate of return on plan assets – overall on bid-value 4.00 2.30 2.00 Plan asset allocation by category (%): 2022 2021 2020 Debt securities and insurance contracts 96 82 86 Equity securities and real estate — 5 10 Cash 4 13 4 100 100 100
Movements in PBO and Fair Value of Plan Assets	Movements in PBO and fair value of UK Plan assets are as follows: (in millions) 2022 2021 Change in PBO: Opening balance $ 679.1 $ 758.7 Interest cost 10.1 7.6 Service cost 2.2 1.6 Benefits paid (45.6 ) (37.3 ) Settlements — (10.6 ) Plan amendments 0.4 5.4 Actuarial losses/(gains) (174.2 ) (40.5 ) Exchange effect (68.0 ) (5.8 ) Closing balance $ 404.0 $ 679.1 Fair value of plan assets: Opening balance $ 838.9 $ 876.7 Benefits paid (45.6 ) (37.3 ) Settlements — (10.6 ) Actual return on assets (258.7 ) 17.5 Exchange effect (82.5 ) (7.4 ) Closing balance $ 452.1 $ 838.9 Net pension asset $ 48.1 $ 159.8
Fair Value of Pension Assets	The fair values of pension assets by level of input were as follows: (in millions) Quoted Prices Significant (Level 2) Significant (Level 3) Total At December 31, 2022 Debt securities: Debt securities issued by non-U.S. $ 4.3 $ $ $ 4.3 Corporate debt securities — Equity backed securities: Other financial derivatives — Other asset backed securities: Insurance contracts 431.8 431.8 Real estate Total assets at fair value 4.3 — 431.8 436.1 Cash 16.0 16.0 Total plan assets $ 20.3 $ — $ 431.8 $ 452.1 (in millions) Quoted Prices Significant (Level 2) Significant (Level 3) Total At December 31, 2021 Debt securities: Debt securities issued by non-U.S. $ 80.3 $ $ $ 80.3 Corporate debt securities 445.7 445.7 Equity backed securities: Other financial derivatives (1.5 ) (1.5 ) Other asset backed securities: Insurance contracts 162.2 162.2 Real estate 47.0 47.0 Total assets at fair value 127.3 444.2 162.2 733.7 Cash 105.2 105.2 Total plan assets $ 232.5 $ 444.2 $ 162.2 $ 838.9 (1) Certain investments that are measured at fair value using the net asset value per share (or its equivalent) have not been categorized in the fair value table with a hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statement of financial position.
Reconciliation of Fair Value of Plan Assets Measured Using Significant Unobservable Inputs	The reconciliation of the fair value of the UK (in millions) Other Assets Balance at December 31, 2020 $ 167.4 Realized/unrealized gains/(losses): Relating to assets still held at the reporting date 3.3 Purchases, issuances and settlements (7.0 ) Exchange effect (1.5 ) Balance at December 31, 2021 $ 162.2 Realized/unrealized gains/(losses): Relating to assets still held at the reporting date (206.6 ) Purchases, issuances and settlements 502.8 Exchange effect (26.6 ) Balance at December 31, 2022 $ 431.8
Plan Net Pension Credit	The projected net periodic benefit for the year ending December 31, 2023 is as follows: (in millions) Service cost $ 3.4 Interest cost on PBO 19.1 Expected return on plan assets (24.5 ) Amortization of prior service credit 0.5 Amortization of actuarial net losses (1.6 ) Net periodic benefit $ (3.1 )
Expected Benefit Payments	The following benefit payments are expected to be made: (in millions) 2023 $ 33.5 2024 $ 33.4 2025 $ 33.3 2026 $ 32.8 2027 $ 32.6 2028-2032 $ 157.2
German Plan [Member]
Movements in PBO and Fair Value of Plan Assets	Movements in PBO of the German plan are as follows: (in millions) 2022 2021 Change in PBO: Opening balance $ 13.2 $ 15.2 Service cost 0.1 0.1 Interest cost 0.1 0.1 Benefits paid (0.3 ) (0.4 ) Actuarial losses/(gains) (4.0 ) (0.7 ) Exchange effect (0.9 ) (1.1 ) Closing balance $ 8.2 $ 13.2
Plan Net Pension Credit	The service cost shown in the table below has been recognized in selling, general and administrative expenses within corporate costs and the other items recognized within other income, net. (in millions) 2022 2021 2020 Service cost $ 0.1 $ 0.1 $ 0.1 Interest cost on PBO 0.1 0.1 0.1 Amortization of actuarial net loss 0.5 1.0 0.8 Net periodic cost $ 0.7 $ 1.2 $ 1.0 Plan assumptions at December 31, (%): Discount rate 3.70 0.90 0.40 Inflation rate 2.25 2.00 1.50 Rate of increase in compensation levels 2.75 2.75 2.75

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Roll-forward of Unrecognized Tax Benefits and Associated Accrued Interest and Penalties	A roll-forward of unrecognized tax benefits and associated accrued interest and penalties is as follows: (in millions) Unrecognised Tax Benefits Interest Total Opening balance at January 1, 2020 $ 14.4 $ 2.0 $ 16.4 Reductions for tax positions of prior periods (1.2 ) (0.2 ) (1.4 ) Additions for tax positions of prior periods 0.4 0.6 1.0 Closing balance at 31 December, 2020 13.6 2.4 16.0 Current — — — Non-current $ 13.6 $ 2.4 $ 16.0 Opening balance at January 1, 2021 $ 13.6 $ 2.4 $ 16.0 Reductions for tax positions of prior periods (1.3 ) 0.0 (1.3 ) Additions for tax positions of prior periods 0.9 0.7 1.6 Closing balance at 31 December, 2021 13.2 3.1 16.3 Current — — — Non-current $ 13.2 $ 3.1 $ 16.3 Opening balance at January 1, 2022 $ 13.2 $ 3.1 $ 16.3 Reductions for tax positions of prior periods (3.1 ) — (3.1 ) Additions for tax positions of prior periods 0.1 0.1 0.2 Closing balance at 31 December, 2022 10.2 3.2 13.4 Current — — — Non-current $ 10.2 $ 3.2 $ 13.4
Sources of Income before Income Taxes	The sources of income before income taxes were as follows: (in millions) 2022 2021 2020 Domestic $ 106.3 $ 53.2 $ (0.7 ) Foreign 78.3 81.2 40.4 $ 184.6 $ 134.4 $ 39.7
Components of Income Tax Expense	The components of income tax expense are summarized as follows: (in millions) 2022 2021 2020 Current: Federal $ 27.0 $ 12.4 $ 6.1 State and local 6.5 2.6 0.5 Foreign 23.1 19.4 6.8 56.6 34.4 13.4 Deferred: Federal (3.7 ) (1.9 ) (2.8 ) State and local (0.7 ) (0.3 ) (0.4 ) Foreign (0.6 ) 9.1 0.8 (5.0 ) 6.9 (2.4 ) $ 51.6 $ 41.3 $ 11.0
Factors Effecting Effective Tax Rate from U.S. Federal Statutory Rate	The effective tax rate varies from the U.S. federal statutory rate because of the factors indicated below: (in percent) 2022 2021 2020 Statutory rate 21.0 % 21.0 % 21.0 % Foreign income inclusions 3.3 1.7 7.1 Foreign tax rate differential 0.9 1.0 4.2 Tax charge/(credit) from previous years 0.2 0.6 3.7 Net charge/(credit) from unrecognized tax benefits (1.4 ) 0.4 (1.7 ) Foreign currency transactions 3.5 0.1 (4.5 ) Tax on unremitted earnings 0.3 0.1 0.3 Non-deductible — — 0.7 Change in U.K. statutory tax rate — 5.4 6.9 State and local taxes 2.2 1.3 1.5 U.S. incentive for foreign derived intangible income (2.7 ) (1.5 ) (1.5 ) Innovation incentives – current year (0.8 ) (1.1 ) (4.9 ) Innovation incentives – prior years — — (5.3 ) Non-deductible 1.4 0.2 1.8 Tax on closure of legacy operations — 1.6 — Other items and adjustments, net 0.1 (0.1 ) (1.6 ) 28.0 % 30.7 % 27.7 %
Details of Deferred Tax Assets and Liabilities	Details of deferred tax assets and liabilities are analyzed as follows: (in millions) 2022 2021 Deferred tax assets: Stock compensation $ 3.7 $ 5.2 Net operating loss carry forwards 10.9 12.0 Other intangible assets 10.5 11.1 Accretion expense 3.2 3.2 Restructuring provision 1.7 2.0 Employee related liabilities 8.1 4.1 Foreign tax credits 0.8 1.9 Operating lease liabilities 11.8 10.6 Inventory provisions 6.6 3.6 Research and experimental expenditure 2.7 — Other 4.8 3.8 Subtotal 64.8 57.5 Less valuation allowance (0.7 ) (0.8 ) Total net deferred tax assets $ 64.1 $ 56.7 Deferred tax liabilities: Property, plant and equipment $ (22.5 ) $ (23.6 ) Intangible assets including goodwill (30.3 ) (29.8 ) Pension asset (10.9 ) (38.2 ) Customer relationships (3.4 ) (4.5 ) Unremitted overseas earnings (1.9 ) (1.9 ) Right-of-use (11.8 ) (10.6 ) Other (3.6 ) (2.5 ) Total deferred tax liabilities $ (84.4 ) $ (111.1 ) Net deferred tax liability $ (20.3 ) $ (54.4 ) Deferred tax assets $ 5.9 $ 6.4 Deferred tax liabilities (26.2 ) (60.8 ) $ (20.3 ) $ (54.4 )

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2022
Debt Disclosure [Abstract]
Summary of Debt Refinancing Costs	The deferred finance costs of $0.6 million (December 31, 2021 – $1.0 million) related to the arrangement of the credit facility, are included within other current and non-current (in millions) 2022 2021 Gross cost at January 1 $ 1.8 $ 1.8 Capitalized in the year — — 1.8 1.8 Accumulated amortization at January 1 $ (0.8 ) $ (0.5 ) Amortization in the year (0.4 ) (0.3 ) $ (1.2 ) $ (0.8 ) Net book value at December 31 $ 0.6 $ 1.0

Plant Closure Provisions (Table

Plant Closure Provisions (Tables)	12 Months Ended
	Dec. 31, 2022
Restructuring and Related Activities [Abstract]
Movements in Plant Closure and Restructuring Provisions	Movements in the provisions are summarized as follows: (in millions) 2022 2021 2020 Total at January 1 $ 56.5 $ 58.5 $ 49.3 Charge for the period excluding restructuring 5.3 3.9 5.1 Restructuring (see Note 5) — — 7.5 Utilized in the period (4.2 ) (5.3 ) (4.1 ) Exchange effect (0.4 ) (0.6 ) 0.7 Total at December 31 57.2 56.5 58.5 Due within one year (5.3 ) (5.2 ) (6.6 ) Due after one year $ 51.9 $ 51.3 $ 51.9

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Carrying Amount and Fair Values of the Company's Assets and Liabilities Measured on a Recurring Basis	The following table presents the carrying amount and fair values of the Company’s assets and liabilities measured on a recurring basis: December 31, 2022 December 31, 2021 (in millions) Carrying Amount Fair Value Carrying Amount Fair Value Assets Non-derivatives: Cash and cash equivalents $ 147.1 $ 147.1 $ 141.8 $ 141.8 Derivatives (Level 1 measurement): Other current and non-current Emissions Trading Scheme credits 2.7 2.7 3.9 3.9 Liabilities Non-derivatives: Finance leases (including current portion) $ — $ — $ 0.1 $ 0.1 Derivatives (Level 1 measurement): Other current liabilities: Foreign currency forward exchange contracts 0.5 0.5 1.2 1.2 Non-financial Stock equivalent units 26.4 26.4 17.3 17.3

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2022
Equity [Abstract]
Stockholders' Equity	Common Stock Treasury Stock (number of shares in thousands) 2022 2021 2020 2022 2021 2020 At January 1 29,554.5 29,554.5 29,554.5 4,781 4,959 5,047 Exercise of options — — — (55 ) (185 ) (109 ) Stock purchases — — — 63 7 21 At December 31 29,554.5 29,554.5 29,554.5 4,789 4,781 4,959

Share-Based Compensation Plans

Share-Based Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2022
Assumptions Used to Determine Grant-Date Fair Value of Options	2022 2021 2020 Dividend yield 1.27 % 1.17 % 1.15 % Expected life 5 years 5 years 5 years Volatility 39.8 % 40.2 % 27.4 % Risk free interest rate 2.90 % 0.45 % 1.10 %
Stock Options Plan [Member]
Summary of Transactions of Company's Stock Option Plans	The following tables summarizes the transactions of the Company’s share-based compensation plans for the year ended December 31, 2022. Number of Weighted Average Grant-Date Fair Value Nonvested at December 31, 2021 680,711 $ 74.6 Granted 332,009 $ 60.2 Vested (178,886 ) $ 72.7 Forfeited (76,794 ) $ 71.2 Nonvested at December 31, 2022 757,040 $ 69.0 Number of Weighted Average Exercise price Outstanding at December 31, 2021 813,971 $ 8.0 Granted 332,009 $ 40.9 Exercised (203,788 ) $ 12.4 Forfeited (77,674 ) $ 2.1 Outstanding at December 31, 2022 864,518 $ 20.1 Exercisable at December 31, 2022 107,478 $ 12.6

Reclassifications out of Accu_2

Reclassifications out of Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2022
Equity [Abstract]
Summary of Reclassifications Out of Accumulated Other Comprehensive Loss	Reclassifications out of accumulated other comprehensive loss (“AOCL”) for 2022 were: (in millions) Amount Affected Line Item in the Details about AOCL Components Defined benefit pension plan items: Amortization of prior service cost $ 0.5 See (1) below Amortization of actuarial net losses 0.5 See (1) below 1.0 Total before tax (0.2 ) Income tax expense Total reclassifications $ 0.8 Net of tax (1) These items are included in the computation of net periodic pension cost. See Note 10 of the Notes to the Consolidated Financial Statements for additional information. Reclassifications out of AOCL for 2021 were: (in millions) Amount Reclassified from AOCL Affected Line Item in the Statement where Details about AOCL Components Defined benefit pension plan items: Amortization of prior service cost $ 0.3 See (1) below Amortization of actuarial net losses 2.6 See (1) below 2.9 Total before tax (0.5 ) Income tax expense Total reclassifications $ 2.4 Net of tax (1) These items are included in the computation of net periodic pension cost. See Note 10 of the Notes to the Consolidated Financial Statements for additional information.
Changes in Accumulated Other Comprehensive Loss	Changes in AOCL for 2022, net of tax, were: (in millions) Defined Cumulative Total Balance at December 31, 2021 $ 10.7 $ (57.6 ) $ (46.9 ) Other comprehensive income/(losses) before reclassifications — (29.2 ) (29.2 ) Amounts reclassified from AOCL 0.8 — 0.8 Actuarial net gains/(losses) arising during the year (69.9 ) — (69.9 ) Net current period other comprehensive income/(losses) (69.1 ) (29.2 ) (98.3 ) Balance at December 31, 2022 $ (58.4 ) $ (86.8 ) $ (145.2 ) Changes in AOCL for 2021, net of tax, were: (in millions) Defined Cumulative Total Balance at December 31, 2020 $ (19.9 ) $ (37.4 ) $ (57.3 ) Other comprehensive income/(losses) before reclassifications — (20.2 ) (20.2 ) Amounts reclassified from AOCL 2.4 — 2.4 Actuarial net gains arising during the year 28.2 — 28.2 Net current period other comprehensive income/(losses) 30.6 (20.2 ) 10.4 Balance at December 31, 2021 $ 10.7 $ (57.6 ) $ (46.9 )

Accounting Policies - Estimated

Accounting Policies - Estimated Useful Lives of Major Classes of Depreciable Assets (Detail)	12 Months Ended
	Dec. 31, 2022
Buildings [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	7 years
Buildings [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	25 years
Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	3 years
Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	10 years

Accounting Policies - Estimat_2

Accounting Policies - Estimated Useful Lives of Major Classes of Assets (Detail)	12 Months Ended
	Dec. 31, 2022
Technology [Member] | Minimum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	10 years
Technology [Member] | Maximum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	17 years
Customer lists [Member] | Minimum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	10 years
Customer lists [Member] | Maximum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	15 years
Brand Names [Member] | Minimum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	5 years
Brand Names [Member] | Maximum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	10 years
Product Rights [Member] | Minimum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	9 years
Product Rights [Member] | Maximum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	10 years
Internally Developed Software [Member] | Minimum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	3 years
Internally Developed Software [Member] | Maximum [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	10 years
Marketing Related [Member]
Other Intangible Assets [Line Items]
finite-lived intangible asset, useful life	11 years

Accounting Policies - Additiona

Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Income tax, Uncertain tax position description	The tax benefits recognized in the financial statements from such positions are then measured based on the largest benefit that has a greater than 50% likelihood of being realized upon settlement.

Segment Reporting - Additional

Segment Reporting - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenue from Contract with Customer, Excluding Assessed Tax	$ 1,963.7	$ 1,483.4	$ 1,193.1
Oilfield Services [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 222.2
Percentage of Revenue from Contract With Customer	11.30%

Segment Reporting and Geograp_3

Segment Reporting and Geographical Area Data - Segment Reporting (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Net sales	$ 1,963.7	$ 1,483.4	$ 1,193.1
Restructuring charge	0	0	(21.3)
Impairment of intangible assets	0	0	(19.8)
Profit on disposal	0	1.8	0
Operating income/(expense)	187.3	132.1	33.7
Identifiable assets at year end	1,603.7	1,570.9	1,397.4
Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	222.2
Operating Segments [Member] | Fuel Specialties [Member]
Segment Reporting Information [Line Items]
Net sales	730.2	618.3	512.7
Operating income/(expense)	121.7	104.6	84.5
Identifiable assets at year end	500.6	571.3	509.7
Operating Segments [Member] | Fuel Specialties [Member] | Refinery and Performance [Member]
Segment Reporting Information [Line Items]
Net sales	552.6	445.3	372.9
Operating Segments [Member] | Fuel Specialties [Member] | Other [Member]
Segment Reporting Information [Line Items]
Net sales	177.6	173	139.8
Operating Segments [Member] | Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales	639.7	525.3	425.4
Operating income/(expense)	95.3	70.9	54.8
Identifiable assets at year end	610.4	469.5	391.5
Operating Segments [Member] | Performance Chemicals [Member] | Personal Care [Member]
Segment Reporting Information [Line Items]
Net sales	393.3	296.1	231.4
Operating Segments [Member] | Performance Chemicals [Member] | Home Care [Member]
Segment Reporting Information [Line Items]
Net sales	94.2	93	87
Operating Segments [Member] | Performance Chemicals [Member] | Other [Member]
Segment Reporting Information [Line Items]
Net sales	152.2	136.2	107
Operating Segments [Member] | Oilfield Services [Member]
Segment Reporting Information [Line Items]
Net sales	593.8	339.8	255
Operating income/(expense)	41.7	10.4	(9.5)
Identifiable assets at year end	297.8	230.8	210.8
Operating Segments [Member] | Octane Additives [Member]
Segment Reporting Information [Line Items]
Operating income/(expense)	0	0	(2.8)
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Corporate costs	(71.4)	(55.6)	(52.2)
Restructuring charge	0	0	(21.3)
Impairment of intangible assets	0	0	(19.8)
Profit on disposal	0	1.8	0
Identifiable assets at year end	$ 194.9	$ 299.3	$ 285.4

Segment Reporting and Geograp_4

Segment Reporting and Geographical Area Data - Segment Reporting on Basis of Geographical Location (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 1,963.7	$ 1,483.4	$ 1,193.1
Income before income taxes	184.6	134.4	39.7
Long-lived assets at year end	310.2	304.9	325.7
Goodwill	358.8	364.3	371.2
Identifiable assets at year end	1,603.7	1,570.9	1,397.4
United States & North America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	1,244.9	821.6	642.4
Income before income taxes	109.1	54.6	0
Long-lived assets at year end	147	137.3	141
Identifiable assets at year end	570.9	464.9	368.8
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	932.5	811.9	689.1
Income before income taxes	42.9	46.1	16.9
Long-lived assets at year end	50.6	55.4	61.3
Identifiable assets at year end	462.3	533.7	455.8
Rest of Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	116.9	115.6	83.4
Income before income taxes	25.5	26.4	19.7
Long-lived assets at year end	112.4	112	123.2
Identifiable assets at year end	164	164.7	171
Rest of World [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	67.7	66.4	45.6
Income before income taxes	7.1	7.3	3.1
Long-lived assets at year end	0.2	0.2	0.2
Identifiable assets at year end	47.7	43.3	30.6
Sales Between Areas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ (398.3)	$ (332.1)	$ (267.4)

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Average number of anti-dilutive options excluded from the calculation of diluted earnings per share	79,145	18,378	17,980

Earnings Per Share - Summary of

Earnings Per Share - Summary of Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Numerator (in millions):
Net income available to common stockholders	$ 133	$ 93.1	$ 28.7
Denominator (in thousands):
Weighted average common shares outstanding	24,787	24,647	24,563
Dilutive effect of stock options and awards	195	207	216
Denominator for diluted earnings per share	24,982	24,854	24,779
Net income per share, basic:	$ 5.37	$ 3.78	$ 1.17
Net income per share, diluted:	$ 5.32	$ 3.75	$ 1.16

Restructuring - Additional Info

Restructuring - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring charges provided for during the period	$ 0	$ 0	$ 21.3
Environment remediation and monitoring costs	0	0	7.5
Impairment of tangible assets	0	$ 0	2
Environmental Monitoring Expense	$ 2
Environmental Remediation Expense, Statement of Income or Comprehensive Income [Extensible Enumeration]	Restructuring charges provided for during the period
Octane Additives [Member] | Operating Segments [Member] | Tetra Ethyl Lead [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges provided for during the period			$ 21.3
Environment remediation and monitoring costs	$ 7.5
Expected loss on contracts	7.2
Impairment of tangible assets	2
Restructuring costs due to downsizing of operations	$ 2.6

Property, Plant and Equipment -

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 512.5	$ 485.4
Accumulated depreciation	(291.6)	(271)
Property, plant and equipment, Net	220.9	214.4
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	20.6	20.7
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	68.7	69.5
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	377.5	371.5
Work in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 45.7	$ 23.7

Property, Plant and Equipment_2

Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Amounts of assets held under finance leases	$ 220.9	$ 214.4
Depreciation charges	25.7	26.3	$ 24.7
Assets Held under Capital Leases [Member]
Property, Plant and Equipment [Line Items]
Amounts of assets held under finance leases	$ 0	$ 0.5

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Leases [Line Items]
Additional leases that have not yet commenced	$ 2.7	$ 8.8
Maximum [Member]
Leases [Line Items]
Operating and finance leases, remaining lease terms	23 years
Minimum [Member]
Leases [Line Items]
Operating and finance leases, remaining lease terms	1 year

Leases - Components of Lease Ex

Leases - Components of Lease Expense (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Finance lease cost:
Amortization of right-of-use assets	$ 0	$ 0.5
Interest on lease liabilities	0	0
Total finance lease cost	0	0.5
Operating lease cost	15.6	13.8
Short-term lease cost	7.2	3.8
Variable lease cost	0.3	0.3
Total lease cost	$ 23.1	$ 18.4

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information Related to Leases (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 23.1	$ 18.1
Operating cash flows from finance leases	0.1	0.5
Financing cash flows from finance leases	0	0
Right-of-use assets obtained in exchange for new lease obligations:
Operating leases	14.9	5.2
Finance leases	$ 0	$ 0

Leases - Supplemental Balance S

Leases - Supplemental Balance Sheet Information Related to Leases (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Operating Leases
Operating lease right-of-use assets	$ 45.3	$ 35.4
Current portion of operating lease liabilities	13.9	12.4
Operating lease liabilities, net of current portion	31.4	23.1
Total operating lease liabilities	45.3	35.5
Finance leases
Property, plant and equipment at cost	512.5	485.4
Accumulated depreciation	(291.6)	(271)
Property, plant and equipment, Net	220.9	214.4
Current portion of finance leases	0	0.1
Total finance lease liabilities	$ 0	$ 0.1
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Current portion of finance leases	Current portion of finance leases
Weighted average remaining lease term
Operating leases	5 years 6 months	4 years 10 months 24 days
Finance leases		6 months
Weighted average discount rate
Operating leases	2.60%	2.50%
Finance leases	0%	2.50%
Financial Leases [Member]
Finance leases
Property, plant and equipment at cost	$ 0	$ 5
Accumulated depreciation	0	(4.5)
Property, plant and equipment, Net	$ 0	$ 0.5

Leases - Maturities of Lease Li

Leases - Maturities of Lease Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Operating Lease Liabilities, Payments Due [Abstract]
Within one year	$ 14.3	$ 12.5
Year two	8.9	9
Year three	6.4	6
Year four	5.2	3.9
Year five	1.5	3.1
Thereafter	13.5	3.2
Total lease payments	49.8	37.7
Less imputed interest	(4.5)	(2.2)
Total operating lease liabilities	45.3	35.5
Finance Lease Liabilities, Payments, Due [Abstract]
Within one year		0.1
Year two		0
Year three		0
Year four		0
Year five		0
Thereafter		0
Total lease payments		0.1
Less imputed interest		0
Total finance lease liabilities	$ 0	$ 0.1

Goodwill - Additional Informati

Goodwill - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Fuel Specialties [Member]
Goodwill [Line Items]
Impairment of goodwill	$ 0	$ 0	$ 0
Performance Chemicals [Member]
Goodwill [Line Items]
Impairment of goodwill	0	0	0
Oilfield Services [Member]
Goodwill [Line Items]
Impairment of goodwill	0	0	0
Octane Additives [Member]
Goodwill [Line Items]
Impairment of goodwill	$ 0	$ 0	$ 0

Goodwill - Summary of Goodwill

Goodwill - Summary of Goodwill (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Line Items]
Gross cost, beginning balance	$ 364.3	$ 371.2
Accumulated impairment losses, beginning balance	0	0
Net book amount, beginning balance	364.3	371.2
Exchange effect	(5.5)	(6.9)
Gross cost, ending balance	358.8	364.3
Accumulated impairment losses, ending balance	0	0
Net book amount, ending balance	358.8	364.3
Performance Chemicals [Member]
Goodwill [Line Items]
Gross cost, beginning balance	111.9	118.5
Accumulated impairment losses, beginning balance	0	0
Net book amount, beginning balance	111.9	118.5
Exchange effect	(5.4)	(6.6)
Gross cost, ending balance	106.5	111.9
Accumulated impairment losses, ending balance	0	0
Net book amount, ending balance	106.5	111.9
Fuel Specialties [Member]
Goodwill [Line Items]
Gross cost, beginning balance	207.6	207.9
Accumulated impairment losses, beginning balance	0	0
Net book amount, beginning balance	207.6	207.9
Exchange effect	(0.1)	(0.3)
Gross cost, ending balance	207.5	207.6
Accumulated impairment losses, ending balance	0	0
Net book amount, ending balance	207.5	207.6
Oilfield Services [Member]
Goodwill [Line Items]
Gross cost, beginning balance	44.8	44.8
Accumulated impairment losses, beginning balance	0	0
Net book amount, beginning balance	44.8	44.8
Exchange effect	0	0
Gross cost, ending balance	44.8	44.8
Accumulated impairment losses, ending balance	0	0
Net book amount, ending balance	$ 44.8	$ 44.8

Other Intangible Assets - Summa

Other Intangible Assets - Summary of Other Intangible Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Gross cost at January 1	$ 295.2	$ 298.9
Additions	2.7	0
Written down in the year	(4.1)	0
Exchange effect	(2.7)	(3.7)
Gross cost at December 31	291.1	295.2	$ 298.9
Accumulated amortization at January 1	(237.7)	(223.6)
Amortization expense	(14)	(16)	(20.9)
Written down in the year	4.1	0
Exchange effect	1.5	1.9
Accumulated amortization at December 31	(246.1)	(237.7)	$ (223.6)
Net book amount at December 31	$ 45	$ 57.5

Other Intangible Assets - Sched

Other Intangible Assets - Schedule of Amortization Expense (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 291.1	$ 295.2	$ 298.9
Accumulated amortization	(246.1)	(237.7)	$ (223.6)
Product Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	34	34
Accumulated amortization	(34)	(31.5)
Brand Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	8.9	8.9
Accumulated amortization	(7.8)	(7.2)
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	55.1	55.1
Accumulated amortization	(40)	(37.7)
Customer and Distributor Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	122.9	125.3
Accumulated amortization	(96.9)	(90.7)
Internally Developed Software [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	45.2	43.1
Accumulated amortization	(42.4)	(41.8)
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	25	28.8
Accumulated amortization	$ (25)	$ (28.8)

Other Intangible Assets - Addit

Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 14	$ 16	$ 20.9
Cost of goods, amortization	2.3	2.3	2.9
Payments to Develop Software	2.7	$ 0	$ 0
Finite-Lived Intangible Assets, Cost Incurred to Renew or Extend	$ 25

Other Intangible Assets - Sch_2

Other Intangible Assets - Schedule of Future Amortization Estimated Expense (Detail) $ in Millions	Dec. 31, 2022 USD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2023	$ 10.6
2024	9.9
2025	6.9
2026	6.8
2027	$ 3.3

Pension and Post-Employment B_3

Pension and Post-Employment Benefits - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Annual cash contribution	$ 0	$ 0
Percentage change in discount rate	0.25%
Amount change in PBO due to discount rate	$ 10.3
Amount change in net pension credit due to discount rate	0.1
Amount change in PBO due to change price inflation	$ 6.5
Percentage change in price inflation	0.25%
Amount change in net pension credit due price inflation	$ 0.6
Maximum percentage of Plan's assets invested in individual company's investment funds	5%
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan settlement benefit obligation	$ 10.6
Other Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount of contributions to defined contribution schemes	11	10.9
Europe [Member] | Performance Chemicals [Member]
Defined Benefit Plan Disclosure [Line Items]
Post-employment obligations European businesses	4.1	$ 4.6
France [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount of unrecognized actuarial net losses, net of tax	$ 0.3
Non-US [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of asset allocation, actual	1%	10%

Pension and Post-Employment B_4

Pension and Post-Employment Benefits - Defined Benefit Pension Plan (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Plan net pension (credit)/charge:
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
United Kingdom Plan [Member]
Plan assumptions at December 31, (%):
Discount rate	4.91%	1.84%	1.36%
Inflation rate	2.85%	3.55%	2.35%
Rate of return on plan assets - overall on bid-value	4%	2.30%	2%
Plan asset allocation by category (%):
Total plan asset allocation by category	100%	100%	100%
United Kingdom Plan [Member] | Cash [Member]
Plan asset allocation by category (%):
Total plan asset allocation by category	4%	13%	4%
United Kingdom Plan [Member] | Defined Benefit Plan Debt Securities And Insurance Contracts [Member]
Plan asset allocation by category (%):
Total plan asset allocation by category	96%	82%	86%
United Kingdom Plan [Member] | Defined Benefit Plan Equity Securities And Real Estate [Member]
Plan asset allocation by category (%):
Total plan asset allocation by category	0%	5%	10%
United Kingdom [Member]
Plan net pension (credit)/charge:
Service cost	$ 3.4
Interest cost on PBO	19.1
Expected return on plan assets	(24.5)
Amortization of prior service cost/(credit)	0.5
Amortization of actuarial net losses	(1.6)
United Kingdom [Member] | United Kingdom Plan [Member]
Plan net pension (credit)/charge:
Service cost	2.2	$ 1.6	$ 1.2
Interest cost on PBO	10.1	7.6	11.2
Expected return on plan assets	(16)	(15.5)	(17.8)
Amortization of prior service cost/(credit)	0.5	0.3	(0.5)
Amortization of actuarial net losses	0	1.6	0.9
Settlement event	0	(0.3)	0
Net periodic benefit	$ (3.2)	$ (4.7)	$ (5)

Pension and Post-Employment B_5

Pension and Post-Employment Benefits - Movements in PBO and Fair Value of Plan Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Change in PBO:
Actuarial losses/(gains)	$ 69.9	$ (28.2)	$ 7.7
Fair value of plan assets:
Opening balance	159.8
Settlements	0	(10.6)
Closing balance	48.1	159.8
United Kingdom Plan [Member]
Change in PBO:
Benefits paid	(45.6)	(37.3)
Fair value of plan assets:
Opening balance	838.9	876.7
Benefits paid	(45.6)	(37.3)
Actual return on assets	(258.7)	17.5
Exchange effect	(82.5)	(7.4)
Closing balance	452.1	838.9	876.7
German Plan [Member]
Change in PBO:
Opening balance	13.2	15.2
Interest cost	0.1	0.1	0.1
Service cost	0.1	0.1	0.1
Benefits paid	(0.3)	(0.4)
Actuarial losses/(gains)	(4)	(0.7)
Exchange effect	(0.9)	(1.1)
Closing balance	8.2	13.2	15.2
Fair value of plan assets:
Benefits paid	(0.3)	(0.4)
Pension Benefit Obligation [Member]
Change in PBO:
Settlements	(10.6)
Pension Benefit Obligation [Member] | United Kingdom Plan [Member]
Change in PBO:
Opening balance	679.1	758.7
Interest cost	10.1	7.6
Service cost	2.2	1.6
Benefits paid	(45.6)	(37.3)
Settlements	0	(10.6)
Plan amendments	0.4	5.4
Actuarial losses/(gains)	(174.2)	(40.5)
Exchange effect	(68)	(5.8)
Closing balance	404	679.1	$ 758.7
Fair value of plan assets:
Benefits paid	$ (45.6)	$ (37.3)

Pension and Post-Employment B_6

Pension and Post-Employment Benefits - Fair Value of Pension Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Fair value of pension assets
Total plan assets	$ 48.1	$ 159.8
Non-US [Member]
Fair value of pension assets
Debt securities	436.1	733.7
Cash	16	105.2
Total plan assets	452.1	838.9
Non-US [Member] | Debt Securities Issued by Non-U.S. Government and Government Agencies [Member]
Fair value of pension assets
Debt securities	4.3	80.3
Non-US [Member] | Corporate Debt Securities [Member]
Fair value of pension assets
Debt securities	0	445.7
Non-US [Member] | Real Estate [Member]
Fair value of pension assets
Debt securities		47
Non-US [Member] | Insurance Contracts [Member]
Fair value of pension assets
Debt securities	431.8	162.2
Non-US [Member] | Other Financial Derivatives [Member]
Fair value of pension assets
Debt securities	0	(1.5)
Non-US [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair value of pension assets
Debt securities	4.3	127.3
Cash	16	105.2
Total plan assets	20.3	232.5
Non-US [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Debt Securities Issued by Non-U.S. Government and Government Agencies [Member]
Fair value of pension assets
Debt securities	4.3	80.3
Non-US [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Real Estate [Member]
Fair value of pension assets
Debt securities		47
Non-US [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair value of pension assets
Debt securities	0	444.2
Total plan assets	0	444.2
Non-US [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate Debt Securities [Member]
Fair value of pension assets
Debt securities		445.7
Non-US [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other Financial Derivatives [Member]
Fair value of pension assets
Debt securities		(1.5)
Non-US [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair value of pension assets
Debt securities	431.8	162.2
Total plan assets	431.8	162.2
Non-US [Member] | Significant Unobservable Inputs (Level 3) [Member] | Insurance Contracts [Member] | Other Asset Backed Securitites [Member]
Fair value of pension assets
Debt securities	$ 431.8	$ 162.2

Pension and Post-Employment B_7

Pension and Post-Employment Benefits - Reconciliation of Fair Value of Plan Assets Measured Using Significant Unobservable Inputs (Detail) - United Kingdom Plan [Member] - Significant Unobservable Inputs (Level 3) [Member] - Other Assets [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 162.2	$ 167.4
Realized/unrealized gains/(losses):
Relating to assets still held at the reporting date	(206.6)	3.3
Purchases, issuances and settlements	502.8	(7)
Exchange effect	(26.6)	(1.5)
Ending balance	$ 431.8	$ 162.2

Pension and Post-Employment B_8

Pension and Post-Employment Benefits - Plan Net Pension Credit (Detail) - United Kingdom Plan [Member] $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3.4
Interest cost on PBO	19.1
Expected return on plan assets	(24.5)
Amortization of prior service credit	0.5
Amortization of actuarial net losses	(1.6)
Net periodic benefit	$ (3.1)

Pension and Post-Employment B_9

Pension and Post-Employment Benefits - Expected Benefit Payments (Detail) - United Kingdom Plan [Member] $ in Millions	Dec. 31, 2022 USD ($)
Defined Benefit Plan Disclosure [Line Items]
2023	$ 33.5
2024	33.4
2025	33.3
2026	32.8
2027	32.6
2028-2032	$ 157.2

Pension and Post-Employment _10

Pension and Post-Employment Benefits - Unfunded Defined Benefit Pension Plan (Detail) - German Plan [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Plan net pension charge:
Service cost	$ 0.1	$ 0.1	$ 0.1
Interest cost on PBO	0.1	0.1	0.1
Amortization of actuarial net loss	0.5	1	0.8
Net periodic benefit	$ 0.7	$ 1.2	$ 1
Plan assumptions at December 31, (%):
Discount rate	3.70%	0.90%	0.40%
Inflation rate	2.25%	2%	1.50%
Rate of increase in compensation levels	2.75%	2.75%	2.75%

Income Taxes - Roll-forward of

Income Taxes - Roll-forward of Unrecognized Tax Benefits and Associated Accrued Interest and Penalties (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Contingency [Line Items]
Opening balance at January 1	$ 16.3	$ 16	$ 16.4
Additions for tax positions of prior periods	0.2	1.6	1
Reductions for tax positions of prior periods	(3.1)	(1.3)	(1.4)
Closing balance at 31 December	13.4	16.3	16
Current	0	0	0
Non-current	13.4	16.3	16
Interest and Penalties [Member]
Income Tax Contingency [Line Items]
Opening balance at January 1	3.1	2.4	2
Additions for tax positions of prior periods	0.1	0.7	0.6
Reductions for tax positions of prior periods	0	0	(0.2)
Closing balance at 31 December	3.2	3.1	2.4
Current	0	0	0
Non-current	3.2	3.1	2.4
Unrecognized Tax Benefits [Member]
Income Tax Contingency [Line Items]
Opening balance at January 1	13.2	13.6	14.4
Additions for tax positions of prior periods	0.1	0.9	0.4
Reductions for tax positions of prior periods	(3.1)	(1.3)	(1.2)
Closing balance at 31 December	10.2	13.2	13.6
Current	0	0	0
Non-current	$ 10.2	$ 13.2	$ 13.6

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Contingency [Line Items]
Unrecognized tax benefits would impact effective tax rate if recognized	$ 13.4
Unrecognized tax benefit	13.4	$ 16.3	$ 16	$ 16.4
Income tax examination interest expense	0.1
Cash payments for income taxes	50	36.8	$ 23.4
Deferred tax assets valuation allowance	0.7	$ 0.8
Foreign exchange movements	0.2
Italian Tax Authorities [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefit	3.2
State [Member] | Certain Losses Upto Two Thousand And Thirty Six And Others Indefinitely [Member]
Income Tax Contingency [Line Items]
Operating loss carry forwards	0.4
Foreign [Member] | Indefinitely [Member]
Income Tax Contingency [Line Items]
Operating loss carry forwards	4.8
United Kingdom [Member] | Foreign [Member] | Profit Diversion Compliance Facility [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefit	0.1
Foreign exchange movements	0.1
Income tax examination penalties and interest expenses	1
United States [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefit	9.2
United States [Member] | Federal [Member] | Indefinitely [Member]
Income Tax Contingency [Line Items]
Operating loss carry forwards	$ 5.1
Non-US [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2011
Non-US [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2014
Non-US [Member] | Historical Impairment Of Subsidiaries [Member]
Income Tax Contingency [Line Items]
Decrease in uncertain tax positions	$ 2.8

Income Taxes - Sources of Incom

Income Taxes - Sources of Income before Income Taxes (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Domestic	$ 106.3	$ 53.2	$ (0.7)
Foreign	78.3	81.2	40.4
Income before income tax expense	$ 184.6	$ 134.4	$ 39.7

Income Taxes - Components of In

Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current:
Federal	$ 27	$ 12.4	$ 6.1
State and local	6.5	2.6	0.5
Foreign	23.1	19.4	6.8
Total Current Income Tax	56.6	34.4	13.4
Deferred:
Federal	(3.7)	(1.9)	(2.8)
State and local	(0.7)	(0.3)	(0.4)
Foreign	(0.6)	9.1	0.8
Total Deferred Income Tax	(5)	6.9	(2.4)
Total	$ 51.6	$ 41.3	$ 11

Income Taxes - Factors Effectin

Income Taxes - Factors Effecting Effective Tax Rate from U.S. Federal Statutory Rate (Detail)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Statutory rate	21%	21%	21%
Foreign income inclusions	3.30%	1.70%	7.10%
Foreign tax rate differential	0.90%	1%	4.20%
Tax charge/(credit) from previous years	0.20%	0.60%	3.70%
Net charge/(credit) from unrecognized tax benefits	(1.40%)	0.40%	(1.70%)
Foreign currency transactions	3.50%	0.10%	(4.50%)
Tax on unremitted earnings	0.30%	0.10%	0.30%
Non-deductible foreign interest	0%	0%	0.70%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent	0%	5.40%	6.90%
State and local taxes	2.20%	1.30%	1.50%
US incentive for foreign derived intangible income	(2.70%)	(1.50%)	(1.50%)
Innovation incentives – current year	(0.80%)	(1.10%)	(4.90%)
Innovation incentives – prior years	0%	0%	(5.30%)
Non-deductible officer compensation	1.40%	0.20%	1.80%
Tax on closure of legacy operations	0%	1.60%	0%
Other items and adjustments, net	0.10%	(0.10%)	(1.60%)
Effective Income Tax Rate	28%	30.70%	27.70%

Income Taxes - Details of Defer

Income Taxes - Details of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Stock compensation	$ 3.7	$ 5.2
Net operating loss carry forwards	10.9	12
Other intangible assets	10.5	11.1
Accretion expense	3.2	3.2
Restructuring provision	1.7	2
Employee related liabilities	8.1	4.1
Foreign tax credits	0.8	1.9
Operating lease liabilities	11.8	10.6
Inventory provisions	6.6	3.6
Research and experimental expenditure	2.7	0
Other	4.8	3.8
Subtotal	64.8	57.5
Less valuation allowance	(0.7)	(0.8)
Total net deferred tax assets	64.1	56.7
Deferred tax liabilities:
Property, plant and equipment	(22.5)	(23.6)
Intangible assets including goodwill	(30.3)	(29.8)
Pension asset	(10.9)	(38.2)
Customer relationships	(3.4)	(4.5)
Unremitted overseas earnings	(1.9)	(1.9)
Right-of-use assets	(11.8)	(10.6)
Other	(3.6)	(2.5)
Total deferred tax liabilities	(84.4)	(111.1)
Net deferred tax liability	(20.3)	(54.4)
Deferred tax assets	5.9	6.4
Deferred tax liabilities	(26.2)	(60.8)
Net deferred tax liability	$ (20.3)	$ (54.4)

Long-Term Debt - Schedule of Lo

Long-Term Debt - Schedule of Long-Term Debt (Parenthetical) (Detail) - Revolving Credit Facility [Member] $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Revolving credit borrowing Capacity	$ 250
Due date of revolving credit	Sep. 25, 2024
Accordion Feature [Member]
Debt Instrument [Line Items]
Revolving credit borrowing Capacity	$ 125

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Amortization of deferred finance costs	$ 0.4	$ 0.3	$ 0.4
Weighted average rate of interest on borrowings	0%	0%
Payments of interest on long-term debt	$ 0	$ 0	0.8
Net cash outflows in respect of refinancing costs	0	0	$ 0.3
Other Current And Non Current Assets [Member]
Debt Instrument [Line Items]
Deferred finance costs, net	0.6	1
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit outstanding	$ 0	$ 0

Long-Term Debt - Summary of Deb

Long-Term Debt - Summary of Debt Refinancing Costs (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Gross cost at January 1	$ 1.8	$ 1.8
Capitalized in the year	0	0
Gross cost	1.8	1.8	$ 1.8
Accumulated amortization,Beginning Balance	(0.8)	(0.5)
Amortization in the year	(0.4)	(0.3)	(0.4)
Accumulated amortization,Ending balance	(1.2)	(0.8)	$ (0.5)
Deferred finance costs, net	$ 0.6	$ 1

Plant Closure Provisions - Move

Plant Closure Provisions - Movements in Plant Closure and Restructuring Provisions (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Restructuring and Related Activities [Abstract]
Beginning Balance	$ 56.5	$ 58.5	$ 49.3
Charge for the period excluding restructuring	5.3	3.9	5.1
Restructuring	0	0	7.5
Utilized in the period	(4.2)	(5.3)	(4.1)
Exchange effect	(0.4)	(0.6)	0.7
Ending Balance	57.2	56.5	58.5
Due within one year	(5.3)	(5.2)	(6.6)
Due after one year	$ 51.9	$ 51.3	$ 51.9

Plant Closure Provisions - Addi

Plant Closure Provisions - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Expenditure	$ 4.2	$ 5.3	$ 4.1
Tetra Ethyl Lead [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Additional provision restructuring charges plant closure		$ 7.5
Remediation [Member]
Restructuring Cost and Reserve [Line Items]
Accretion expense recognized	3.8
Remediation charge for changes in the scope and cost of future remediation activities	$ 1.5

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Amount and Fair Values of the Company's Assets and Liabilities Measured on a Recurring Basis (Detail) - Recurring [Member] - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Carrying Amount [Member]
Non-derivatives:
Cash and cash equivalents	$ 147.1	$ 141.8
Non-derivatives:
Finance leases (including current portion)	0	0.1
Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign Currency Forward Exchange Contracts [Member]
Derivatives (Level 1 measurement):
Foreign currency forward exchange contracts	0.5	1.2
Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Emission Trading Scheme Credits [Member]
Derivatives (Level 1 measurement):
Emissions Trading Scheme credits	2.7	3.9
Carrying Amount [Member] | Significant Unobservable Inputs (Level 3) [Member]
Non-financial liabilities (Level 3 measurement):
Stock equivalent units	26.4	17.3
Fair Value [Member]
Non-derivatives:
Cash and cash equivalents	147.1	141.8
Non-derivatives:
Finance leases (including current portion)	0	0.1
Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign Currency Forward Exchange Contracts [Member]
Derivatives (Level 1 measurement):
Foreign currency forward exchange contracts	0.5	1.2
Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Emission Trading Scheme Credits [Member]
Derivatives (Level 1 measurement):
Emissions Trading Scheme credits	2.7	3.9
Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member]
Non-financial liabilities (Level 3 measurement):
Stock equivalent units	$ 26.4	$ 17.3

Derivative Instruments and Ri_2

Derivative Instruments and Risk Management - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Interest rate swaps notional value	$ 0	$ 0
Foreign currency forward exchange contracts notional value	$ 161.1	113
Maximum [Member]
Derivative [Line Items]
Maturity period of foreign currency forward exchange contracts	1 year
Emission Trading Scheme Credits [Member] | UNITED KINGDOM
Derivative [Line Items]
Commodity contract asset non current	$ 2.7	3.9
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	$ 0.7	$ 1

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Other Commitments [Line Items]
Guarantees	$ 7	$ 4.6
Minimum [Member]
Other Commitments [Line Items]
Fixed maturity guarantee remaining term	1 month
Maximum [Member]
Other Commitments [Line Items]
Fixed maturity guarantee remaining term	4 years
Additional Cost To Complete Wip [Member]
Other Commitments [Line Items]
Capital commitments	$ 37.7	23.5
Additional Cost To Complete Wip [Member] | Computer Software, Intangible Asset [Member]
Other Commitments [Line Items]
Capital commitments	$ 25	$ 0

Stockholders' Equity - Stockhol

Stockholders' Equity - Stockholder's Equity (Detail) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Equity [Abstract]
Common Stock, Beginning balance	29,554,500	29,554,500	29,554,500
Exercise of options, Common Stock
Stock purchases, Common Stock
Common Stock, Ending balance	29,554,500	29,554,500	29,554,500
Treasury Stock, Beginning balance	4,780,806	4,959,000	5,047,000
Exercise of options, Treasury Stock	(55,000)	(185,000)	(109,000)
Stock purchases, Treasury Stock	63,000	7,000	21,000
Ending balance, Treasury Stock	4,788,966	4,780,806	4,959,000

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - shares	Dec. 31, 2022	Dec. 31, 2021
Equity [Abstract]
Common stock, shares authorized	40,000,000	40,000,000

Share-Based Compensation Plan_2

Share-Based Compensation Plans - Additional Information (Detail) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($) Employees Employee	Dec. 31, 2022 USD ($) Stock_Plan $ / shares shares	Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option compensation		$ 6.7	$ 4.4	$ 5.8
Total compensation cost related to non-vested stock options not yet recognized		$ 23.1
Expected compensation cost recognized over the weighted-average period		1 year 10 months 24 days
Accrued liabilities		$ 202.9	166.5
Share-Based Payment Arrangement, Expense, after Tax		$ 0.7
Stock Options Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period	2 years
Expiration term for stock granted		10 years
Aggregate number of shares of common stock reserved for issuance which can be granted | shares		2,550,000
Number of stock option plans | Stock_Plan		2
Stock option compensation		$ 6.7	4.4	5.8
Current tax benefit related to stock option compensation			1.3	1.6
Share-based Goods and Nonemployee Services Transaction, Modification of Terms, Incremental Compensation Cost	$ 2.4
Number of Grantees Affected | Employee	14
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value | $ / shares		$ 72.7
Stock Options Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period		2 years
Stock Options Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period		5 years
Stock Equivalent Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period	2 years
Expiration term for stock granted		10 years
Total intrinsic value exercised		$ 18.1
Accrued liabilities			26.4
Compensation cost		$ 24.2	$ 3.1	$ 1.9
Number of Grantees Affected | Employees	61
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value | $ / shares		$ 60.2	$ 84.8	$ 72.4
Total intrinsic value of options outstanding		$ 71.5
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value		9.7
ProceedsFromStockOptionsExercised		15
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value		$ 13
Stock Equivalent Units [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period		6 months
Stock Equivalent Units [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period		5 years

Share-Based Compensation Plan_3

Share-Based Compensation Plans - Assumptions Used to Determine Grant-Date Fair Value of Options (Detail) - Black-Scholes Model [Member]	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	1.27%	1.17%	1.15%
Expected life	5 years	5 years	5 years
Volatility	39.80%	40.20%	27.40%
Risk free interest rate	2.90%	0.45%	1.10%

Share-Based Compensation Plan_4

Share-Based Compensation Plans - Summary of Transactions of The Share Based Compensation Plans (Detail)	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Granted | shares	332,009
Number of shares, Exercised | shares	(203,788)
Outstanding at December 31, 2021 | shares	813,971
Number of shares, Forfeited | shares	(77,674)
Outstanding at December 31, 2022 | shares	864,518
Exercisable at December 31, 2022 | shares	107,478
Outstanding, Weighted Average Exercise Price, Beginning balance | $ / shares	$ 8
Granted, Weighted Average Exercise Price | $ / shares	40.9
Exercised, Weighted Average Exercise Price | $ / shares	12.4
Forfeited, Weighted Average Exercise Price | $ / shares	2.1
Outstanding, Weighted Average Exercise Price, Ending balance | $ / shares	20.1
Weighted Average Exercise price , Exercisable | $ / shares	$ 12.6
Stock Options Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Begining balance | shares	680,711
Number of shares, Granted | shares	332,009
Number of shares, Vested | shares	(178,886)
Number of shares, Forfeited | shares	(76,794)
Number of shares , Ending balance | shares	757,040
Weighted Average Grant-Date Fair Value , Begining balance | $ / shares	$ 74.6
Weighted Average Grant-Date Fair Value, Granted | $ / shares	60.2
Weighted Average Grant-Date Fair Value, Vested | $ / shares	72.7
Weighted Average Grant-Date Fair Value, Forfeited | $ / shares	71.2
Weighted Average Grant-Date Fair Value, Ending balance | $ / shares	$ 69

Reclassifications out of Accu_3

Reclassifications out of Accumulated Other Comprehensive Loss - Summary of Reclassifications out of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications	$ (0.8)	$ (2.4)
Defined Benefit Pension Plan Items [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassifications	(0.8)	(2.4)
Reclassification Out of Accumulated Other Comprehensive Income/(Loss) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	1	2.9
Income tax expense	(0.2)	(0.5)
Total reclassifications	0.8	2.4
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 cost	0.5	0.3
Amortization of actuarial net losses	$ 0.5	$ 2.6

Reclassifications out of Accu_4

Reclassifications out of Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 1,032.4
Other comprehensive income/(losses) before reclassifications	(29.2)	$ (20.2)
Amounts reclassified from AOCL	0.8	2.4
Actuarial net gains/(losses) arising during the year	(69.9)	28.2	$ (7.7)
Net current period other comprehensive income/(losses)	(98.3)	10.4
Ending Balance	1,038	1,032.4
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(46.9)	(57.3)
Actuarial net gains/(losses) arising during the year	(69.9)	28.2	(7.7)
Ending Balance	(145.2)	(46.9)	(57.3)
Defined Benefit Pension Plan Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	10.7	(19.9)
Other comprehensive income/(losses) before reclassifications
Amounts reclassified from AOCL	0.8	2.4
Actuarial net gains/(losses) arising during the year	(69.9)	28.2
Net current period other comprehensive income/(losses)	(69.1)	30.6
Ending Balance	(58.4)	10.7	(19.9)
Foreign Currency Translation Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(57.6)	(37.4)
Other comprehensive income/(losses) before reclassifications	(29.2)	(20.2)
Amounts reclassified from AOCL
Actuarial net gains/(losses) arising during the year
Net current period other comprehensive income/(losses)	(29.2)	(20.2)
Ending Balance	$ (86.8)	$ (57.6)	$ (37.4)

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Smith, Gambrell & Russell, LLP [Member]
Related Party Transaction [Line Items]
Fees payable to Smith, Gambrell & Russell	$ 0.3	$ 0.1	$ 0.8
Amount due to related party	0	0
European Metal Recycling Limited [Member]
Related Party Transaction [Line Items]
Amount due to related party	0	0
Tendering process to select best buyer of scrap metal	0.1	0.6	$ 0.2
Advan Six [Member]
Related Party Transaction [Line Items]
Amount due to related party	0	0.1
Tendering process to select best buyer of scrap metal	$ 0.5	$ 0.4