Ecovyst (ECVT) 10-Q 2 Aug 24 2024 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2024	Jul. 26, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	001-38221
Entity Registrant Name	Ecovyst Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-3406833
Entity Address, Address Line One	300 Lindenwood Drive
Entity Address, City or Town	Malvern
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19355
City Area Code	(484)
Local Phone Number	617-1200
Title of 12(b) Security	Common stock, par value $0.01 per share
Trading Symbol	ECVT
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		116,466,232
Entity Central Index Key	0001708035
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q2
Amendment Flag	false

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Sales	$ 182,820	$ 184,110	$ 343,357	$ 344,984
Cost of goods sold	129,157	123,140	250,471	247,520
Gross profit	53,663	60,970	92,886	97,464
Selling, general and administrative expenses	22,707	21,395	44,310	42,514
Other operating expense, net	3,108	6,262	6,774	12,980
Operating income	27,848	33,313	41,802	41,970
Equity in net (income) from affiliated companies	(1,392)	(11,374)	(3,464)	(11,597)
Interest expense, net	12,895	9,168	26,304	19,000
Debt extinguishment costs	4,560	0	4,560	0
Other expense, net	410	610	627	182
Income before income taxes	11,375	34,909	13,775	34,385
Provision for income taxes	3,080	8,787	4,259	9,734
Net income	$ 8,295	$ 26,122	$ 9,516	$ 24,651
Net income per share:
Basic income per share (in dollars per share)	$ 0.07	$ 0.22	$ 0.08	$ 0.20
Diluted income per share (in dollars per share)	$ 0.07	$ 0.22	$ 0.08	$ 0.20
Weighted average shares outstanding:
Basic (in shares)	116,912,332	118,651,402	116,935,708	120,335,414
Diluted (in shares)	117,635,289	119,920,742	117,545,240	121,831,942

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 8,295	$ 26,122	$ 9,516	$ 24,651
Other comprehensive income (loss), net of tax:
Pension and postretirement benefits	530	465	524	441
Net (loss) gain from hedging activities	(1,075)	5,399	2,789	(2,521)
Foreign currency translation	(679)	828	(2,363)	3,013
Total other comprehensive (loss) income	(1,224)	6,692	950	933
Comprehensive income	$ 7,071	$ 32,814	$ 10,466	$ 25,584

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
ASSETS
Cash and cash equivalents	$ 83,318	$ 88,365
Accounts receivable, net	85,218	81,314
Inventories, net	52,027	45,115
Derivative assets	12,270	13,419
Prepaid and other current assets	31,123	17,774
Total current assets	263,956	245,987
Investments in affiliated companies	409,187	440,198
Property, plant and equipment, net	573,559	576,904
Goodwill	404,275	404,470
Other intangible assets, net	109,422	116,550
Right-of-use lease assets	24,301	24,281
Other long-term assets	35,239	29,361
Total assets	1,819,939	1,837,751
LIABILITIES
Current maturities of long-term debt	6,548	9,000
Accounts payable	34,195	40,195
Operating lease liabilities—current	7,740	8,193
Accrued liabilities	48,544	61,693
Total current liabilities	97,027	119,081
Long-term debt, excluding current portion	855,857	858,946
Deferred income taxes	115,183	115,791
Operating lease liabilities—noncurrent	16,419	16,030
Other long-term liabilities	18,170	22,439
Total liabilities	1,102,656	1,132,287
Commitments and contingencies (Note 15)
EQUITY
Common stock ($0.01 par); authorized shares 450,000,000; issued shares 140,872,846 and 140,744,045 on June 30, 2024 and December 31, 2023, respectively; outstanding shares 116,466,232 and 116,116,895 on June 30, 2024 and December 31, 2023, respectively	1,409	1,407
Preferred stock ($0.01 par); authorized shares 50,000,000; no shares issued or outstanding on June 30, 2024 and December 31, 2023	0	0
Additional paid-in capital	1,100,749	1,102,581
Accumulated deficit	(161,340)	(170,856)
Treasury stock, at cost; shares 24,406,614 and 24,627,150 on June 30, 2024 and December 31, 2023, respectively	(223,527)	(226,710)
Accumulated other comprehensive loss	(8)	(958)
Total equity	717,283	705,464
Total liabilities and equity	$ 1,819,939	$ 1,837,751

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Common stock, par (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares (in shares)	450,000,000	450,000,000
Common stock, issued shares (in shares)	140,872,846	140,744,045
Common stock, outstanding shares (in shares)	116,466,232	116,116,895
Preferred stock, par (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized shares (in shares)	50,000,000	50,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Treasury stock (in shares)	24,406,614	24,627,150

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	(Accumulated deficit)	Treasury stock, at cost	Accumulated other comprehensive income
Beginning balance at Dec. 31, 2022	$ 707,229	$ 1,396	$ 1,091,475	$ (242,010)	$ (149,624)	$ 5,992
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (loss)	(1,471)			(1,471)
Other comprehensive (loss) income	(5,759)					(5,759)
Repurchases of common shares	(29,850)				(29,850)
Tax withholdings on equity award vesting	(866)				(866)
Stock compensation expense	4,756		4,756
Shares issued under equity incentive plan, net of forfeitures	112	10	102
Ending balance at Mar. 31, 2023	674,151	1,406	1,096,333	(243,481)	(180,340)	233
Beginning balance at Dec. 31, 2022	707,229	1,396	1,091,475	(242,010)	(149,624)	5,992
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (loss)	24,651
Other comprehensive (loss) income	933
Tax withholdings on equity award vesting	(866)
Ending balance at Jun. 30, 2023	667,764	1,407	1,101,285	(217,359)	(224,494)	6,925
Beginning balance at Mar. 31, 2023	674,151	1,406	1,096,333	(243,481)	(180,340)	233
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (loss)	26,122			26,122
Other comprehensive (loss) income	6,692					6,692
Repurchases of common shares	(43,524)				(43,524)
Excise tax on repurchases of common shares	(630)				(630)
Stock compensation expense	4,739		4,739
Shares issued under equity incentive plan, net of forfeitures	214	1	213
Ending balance at Jun. 30, 2023	667,764	1,407	1,101,285	(217,359)	(224,494)	6,925
Beginning balance at Dec. 31, 2023	705,464	1,407	1,102,581	(170,856)	(226,710)	(958)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (loss)	1,221			1,221
Other comprehensive (loss) income	2,174					2,174
Tax withholdings on equity award vesting	(1,218)				(1,218)
Stock compensation expense	3,674		3,674
Shares issued under equity incentive plan, net of forfeitures	41	2	(9,290)		9,329
Ending balance at Mar. 31, 2024	711,356	1,409	1,096,965	(169,635)	(218,599)	1,216
Beginning balance at Dec. 31, 2023	705,464	1,407	1,102,581	(170,856)	(226,710)	(958)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (loss)	9,516
Other comprehensive (loss) income	950
Tax withholdings on equity award vesting	(1,218)
Ending balance at Jun. 30, 2024	717,283	1,409	1,100,749	(161,340)	(223,527)	(8)
Beginning balance at Mar. 31, 2024	711,356	1,409	1,096,965	(169,635)	(218,599)	1,216
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (loss)	8,295			8,295
Other comprehensive (loss) income	(1,224)					(1,224)
Repurchases of common shares	(5,010)				(5,010)
Stock compensation expense	3,827		3,827
Shares issued under equity incentive plan, net of forfeitures	39	0	(43)
Ending balance at Jun. 30, 2024	$ 717,283	$ 1,409	$ 1,100,749	$ (161,340)	$ (223,527)	$ (8)

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash flows from operating activities:
Net income	$ 9,516	$ 24,651
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	36,523	34,147
Amortization	7,034	7,019
Amortization of deferred financing costs and original issue discount	1,052	1,024
Debt extinguishment costs	90	0
Foreign currency exchange loss (gain)	155	(632)
Deferred income tax (benefit) provision	(1,690)	1,283
Net loss on asset disposals	614	2,306
Stock compensation	7,507	9,070
Equity in net income from affiliated companies	(3,464)	(11,597)
Dividends received from affiliated companies	33,000	10,000
Other, net	2,216	6,255
Working capital changes that used cash:
Receivables	(4,076)	(3,019)
Inventories	(6,693)	(2,987)
Prepaids and other current assets	(4,457)	(5,724)
Accounts payable	(3,289)	(1,468)
Accrued liabilities	(27,578)	(29,188)
Net cash provided by operating activities	46,460	41,140
Cash flows from investing activities:
Purchases of property, plant and equipment	(36,649)	(39,227)
Other, net	(200)	0
Net cash used in investing activities	(36,849)	(39,227)
Cash flows from financing activities:
Draw down of revolving credit facilities	0	14,500
Repayments of revolving credit facilities	0	(14,500)
Issuance of long-term debt, net of discount	870,817	0
Repayments of long-term debt	(877,500)	(4,500)
Repurchases of common shares	(5,010)	(73,373)
Tax withholdings on equity award vesting	(1,218)	(866)
Repayment of financing obligation	(1,478)	(1,433)
Other, net	41	294
Net cash used in financing activities	(14,348)	(79,878)
Effect of exchange rate changes on cash and cash equivalents	(310)	(3,723)
Net change in cash and cash equivalents	(5,047)	(81,688)
Cash and cash equivalents at beginning of period	88,365	110,920
Cash and cash equivalents at end of period	$ 83,318	$ 29,232

Background and Basis of Present

Background and Basis of Presentation	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Background and Basis of Presentation	1. Background and Basis of Presentation: Description of Business Ecovyst Inc. and subsidiaries (the “Company” or “Ecovyst”) is a leading integrated and innovative global provider of advanced materials, specialty catalysts and services. The Company supports customers globally through its strategically located network of manufacturing facilities. The Company believes that its products and services contribute to improving the sustainability of the environment. The Company has two uniquely positioned specialty businesses: Ecoservices provides sulfuric acid recycling to the North American refining industry for the production of alkylate and provides high quality and high strength virgin sulfuric acid for industrial and mining applications. Ecoservices also provides chemical waste handling and treatment services, as well as ex-situ catalyst activation services for the refining and petrochemical industry. Advanced Materials & Catalysts, through its Advanced Silicas business, provides finished silica catalysts, catalyst supports and functionalized silicas necessary to produce high performing plastics and to enable sustainable chemistry, and through the Zeolyst Joint Venture, innovates and supplies specialty zeolites used for catalysts that support the production of sustainable fuels, remove nitrogen oxides from diesel engine emissions and that are broadly applied in refining and petrochemical processes. The Company’s regeneration services product group, which is a part of the Company’s Ecoservices segment, typically experiences seasonal fluctuations as a result of higher demand for gasoline products in the summer months and lower demand in the winter months. These demand fluctuations result in higher sales and working capital requirements in the second and third quarters. Basis of Presentation The condensed consolidated financial statements included herein are unaudited. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) have been condensed or omitted pursuant to such rules and regulations for interim reporting. In the opinion of management, all adjustments of a normal and recurring nature necessary to state fairly the financial position and results of operations have been included. The results of operations are not necessarily indicative of the expected results for the full year. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023.

New Accounting Standards

New Accounting Standards	6 Months Ended
	Jun. 30, 2024
Accounting Standards Update and Change in Accounting Principle [Abstract]
New Accounting Standards	2. New Accounting Standards: Accounting Standards Not Yet Adopted In November 2023, the Financial Accounting Standards Board (“FASB”) issued guidance to improve the disclosures related to public business entities reportable segments. This new guidance requires entities to provide information regarding significant segment expenses, especially those segment expenses that are regularly reported to the Company’s chief operating decision maker (the Company’s Chief Executive Officer), or CODM. The guidance also require public entities to disclose the nature, type and amounts of other segment items by reportable segment. Public business entities will also have to report all annual disclosures about segments profits or losses that are required by ASC 280 on an interim basis, including the significant segment expenses and other segment items. The new guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The disclosure will be implemented as required for the fiscal year ended December 31, 2024. The Company is currently evaluating the impact of this guidance. In December 2023, FASB issued guidance to improve disclosures related to incomes taxes. This new guidance requires public business entities to disaggregate information on the effective tax rate reconciliation and income taxes paid to provide greater transparency. Public business entities will be required to provide additional information in specified categories related to effective tax rate reconciliation in tabular form and provide income taxes paid by jurisdictions, with further disaggregation needed if amounts exceed 5% of the total. The new guidance is effective for fiscal years beginning after December 15, 2024. The disclosure will be implemented as required for the fiscal year ended December 31, 2025. The Company is currently evaluating the impact of this guidance. In October 2023, FASB issued guidance to amend either presentation or disclosure requirements related to fourteen subtopics in the FASB Accounting Standards Codification, that are currently in the SEC Regulation S-X or Regulation S-K. The new guidance was issued in response to the SEC’s ruling on disclosure simplification. For entities subject to existing SEC disclosure requirements, the effective date of each amendment of the topics will be the date that the SEC removes the related disclosure from Regulation S-X or Regulation S-K. The guidance must be applied prospectively, with no early adoption permitted for entities subject to those existing SEC disclosures. The Company is currently evaluating the impact of the new guidance as it pertains to the fourteen subtopics that would impact the business and will apply prospectively once in effect. In August 2023, the FASB issued guidance for entities that meet the definition of a joint venture or a corporate joint venture, to adopt a new basis of accounting upon the formation of the joint venture. The new guidance requires the initial measurement of contributed net assets and liabilities at fair value on the formation date, recognition of goodwill for the difference between the fair value of the joint venture’s equity and net assets, and disclosures about the nature and financial impact of the transaction. The new guidance requires prospective application and is effective for all joint ventures that are formed on or after January 1, 2025, with early adoption permitted. Joint ventures that formed before January 1, 2025 may elect to retrospectively apply the new guidance. The Company will apply the guidance to any new joint ventures formed after the effective date.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	6 Months Ended
	Jun. 30, 2024
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	3. Revenue from Contracts with Customers: Disaggregated Revenue The Company’s primary means of disaggregating revenues is by reportable segments, which can be found in Note 17 to these condensed consolidated financial statements. The Company’s portfolio of products is integrated into a variety of end uses, which are described in the table below. Key End Uses Key Products Clean fuels, emission control & other • Refining hydrocracking catalysts • Emission control catalysts • Catalyst supports used in production of sustainable fuels such as renewable diesel • Catalysts used in production of sustainable aviation fuels • Catalyst activation • Aluminum sulfate solution • Ammonium bisulfite solution Polyethylene, polymers & engineered plastics • Catalysts for high-density polyethylene and chemicals syntheses • Antiblock for film packaging • Catalyst for advanced recycling Regeneration and treatment services • Sulfuric acid regeneration services • Treatment services Industrial, mining & automotive • Virgin sulfuric acid for mining • Virgin sulfuric derivatives for industrial production • Virgin sulfuric derivatives for nylon production The following tables disaggregate the Company’s sales, by segment and end uses, for the three and six months ended June 30, 2024 and 2023, respectively: Three months ended June 30, 2024 Ecoservices Advanced Materials & Catalysts (2) Total Clean fuels, emission control & other $ 8,614 $ — $ 8,614 Polyethylene, polymers & engineered plastics — 28,862 28,862 Regeneration and treatment services (1) 95,365 — 95,365 Industrial, mining & automotive 49,979 — 49,979 Total segment sales $ 153,958 $ 28,862 $ 182,820 Three months ended June 30, 2023 Ecoservices Advanced Materials & Catalysts (2) Total Clean fuels, emission control & other $ 8,426 $ — $ 8,426 Polyethylene, polymers & engineered plastics — 26,045 26,045 Regeneration and treatment services (1) 98,494 — 98,494 Industrial, mining & automotive 51,145 — 51,145 Total segment sales $ 158,065 $ 26,045 $ 184,110 Six months ended June 30, 2024 Ecoservices Advanced Materials & Catalyst (2) Total Clean fuels, emission control & other $ 16,003 $ — $ 16,003 Polyethylene, polymers & engineered plastics — 47,797 47,797 Regeneration and treatment services (1) 178,684 — 178,684 Industrial, mining & automotive 100,873 — 100,873 Total segment sales $ 295,560 $ 47,797 $ 343,357 Six months ended June 30, 2023 Ecoservices Advanced Materials & Catalyst (2) Total Clean fuels, emission control & other $ 13,166 $ — $ 13,166 Polyethylene, polymers & engineered plastics — 49,179 49,179 Regeneration and treatment services (1) 186,838 — 186,838 Industrial, mining & automotive 95,801 — 95,801 Total segment sales $ 295,805 $ 49,179 $ 344,984 (1) As described in Note 1 to these condensed consolidated financial statements, the Company experiences seasonal s ales fluctuations to customers in the regeneration services product group. (2) Excludes the Company’s proportionate share of sales from the Zeolyst International and Zeolyst C.V. joint ventures (collectively, the “Zeolyst Joint Venture”) accounted for using the equity method (see Note 9 to these condensed consolidated financial statements for further information).

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. Fair Value Measurements: Fair values are based on quoted market prices when available. When market prices are not available, fair values are generally estimated using discounted cash flow analyses, incorporating current market inputs for similar financial instruments with comparable terms and credit quality. In instances where there is little or no market activity for the same or similar instruments, the Company estimates fair values using methods, models and assumptions that management believes a hypothetical market participant would use to determine a current transaction price. These valuation techniques involve some level of management estimation and judgment that becomes significant with increasingly complex instruments or pricing models. Where appropriate, adjustments are included to reflect the risk inherent in a particular methodology, model or input used. The Company’s financial assets and liabilities carried at fair value have been classified based upon a fair value hierarchy. The hierarchy gives the highest ranking to fair values determined using unadjusted quoted prices in active markets for identical assets and liabilities (Level 1) and the lowest ranking to fair values determined using methodologies and models with unobservable inputs (Level 3). The classification of an asset or a liability is based on the lowest level input that is significant to its measurement. For example, a Level 3 fair value measurement may include inputs that are both observable (Levels 1 and 2) and unobservable (Level 3). The levels of the fair value hierarchy are as follows: • Level 1—Values are unadjusted quoted prices for identical assets and liabilities in active markets accessible at the measurement date. Active markets provide pricing data for trades occurring at least weekly and include exchanges and dealer markets. • Level 2—Inputs include quoted prices for similar assets or liabilities in active markets, quoted prices from those willing to trade in markets that are not active, or other inputs that are observable or can be corroborated by market data for the term of the instrument. Such inputs include market interest rates and volatilities, spreads and yield curves. • Level 3—Certain inputs are unobservable (supported by little or no market activity) and significant to the fair value measurement. Unobservable inputs reflect the Company’s best estimate of what hypothetical market participants would use to determine a transaction price for the asset or liability at the reporting date. The following tables present information about the Company’s assets and liabilities that were measured at fair value on a recurring basis as of June 30, 2024 and December 31, 2023, and indicates the fair value hierarchy of the valuation techniques the Company utilized to determine such fair value. June 30, Quoted Prices in Significant Other Significant Derivative assets: Interest rate caps (Note 12) $ 19,965 $ — $ 19,965 $ — Derivative liabilities: Interest rate caps (Note 12) $ 403 $ — $ 403 $ — December 31, Quoted Prices in Significant Other Significant Derivative assets: Interest rate caps (Note 12) $ 19,021 $ — $ 19,021 $ — Derivative liabilities: Interest rate caps (Note 12) $ 2,496 $ — $ 2,496 $ — Derivative contracts Derivative assets and liabilities can be exchange-traded or traded over-the-counter (“OTC”). The Company generally values exchange-traded derivatives using models that calibrate to market transactions and eliminate timing differences between the closing price of the exchange-traded derivatives and their underlying instruments. OTC derivatives are valued using market transactions and other market evidence whenever possible, including market-based inputs to models, model calibration to market transactions, broker or dealer quotations or alternative pricing sources with reasonable levels of price transparency. When models are used, the selection of a particular model to value an OTC derivative depends on the contractual terms of, and specific risks inherent in, the instrument as well as the availability of pricing information in the market. The Company generally uses similar models to value similar instruments. Valuation models require a variety of inputs, including contractual terms, market prices and rates, forward curves, measures of volatility, and correlations of such inputs. For OTC derivatives that trade in liquid markets, such as forward contracts, swaps and options, model inputs can generally be corroborated by observable market data by correlation or other means, and model selection does not involve significant management judgment. As of June 30, 2024, th e Company had interest rate c aps th at were fair valued using Level 2 inputs. In addition, the Company applies a credit valuation adjustment to reflect credit risk which is calculated based on credit default swaps. To the extent that the Company’s net exposure under a specific master agreement is an asset, the Company utilizes the counterparty’s default swap rate. If the net exposure under a specific master agreement is a liability, the Company utilizes a default swap rate comparable to Ecovyst. The credit valuation adjustment is added to the discounted fair value to reflect the exit price that a market participant would be willing to receive to assume the Company’s liabilities or that a market participant would be willing to pay for the Company’s assets.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2024
Equity [Abstract]
Stockholders' Equity	5. Stockholders' Equity: Accumulated Other Comprehensive Income (Loss) The following tables present the tax effects of each component of other comprehensive income (loss) for the three and six months ended June 30, 2024 and 2023, respectively: Three months ended June 30, 2024 2023 Pre-tax Tax benefit/ After-tax amount Pre-tax Tax benefit/ After-tax amount Defined benefit and other postretirement plans: Net gain $ 714 $ (178) $ 536 $ 651 $ (162) $ 489 Net prior service cost (7) 1 (6) (31) 7 (24) Benefit plans, net 707 (177) 530 620 (155) 465 Net (loss) gain from hedging activities (1,433) 358 (1,075) 7,059 (1,660) 5,399 Foreign currency translation (679) — (679) 828 — 828 Other comprehensive income (loss) $ (1,405) $ 181 $ (1,224) $ 8,507 $ (1,815) $ 6,692 Six months ended June 30, 2024 2023 Pre-tax Tax benefit/ After-tax amount Pre-tax Tax benefit/ After-tax amount Defined benefit and other postretirement plans: Net gain $ 713 $ (178) $ 535 $ 650 $ (162) $ 488 Net prior service cost (15) 4 (11) (62) 15 (47) Benefit plans, net 698 (174) 524 588 (147) 441 Net gain (loss) from hedging activities 3,719 (930) 2,789 (3,244) 723 (2,521) Foreign currency translation (2,363) — (2,363) 3,013 — 3,013 Other comprehensive income $ 2,054 $ (1,104) $ 950 $ 357 $ 576 $ 933 The following tables present the changes in accumulated other comprehensive income (loss), net of tax, by component for the six months ended June 30, 2024 and 2023, respectively: Defined benefit Net gain (loss) Foreign Total December 31, 2023 $ 612 $ 12,546 $ (14,116) $ (958) Other comprehensive income (loss) before reclassifications 540 9,778 (2,363) 7,955 Amounts reclassified from accumulated other comprehensive loss (1) (16) (6,989) — (7,005) Net current period other comprehensive income (loss) 524 2,789 (2,363) 950 June 30, 2024 $ 1,136 $ 15,335 $ (16,479) $ (8) December 31, 2022 $ (508) $ 24,672 $ (18,172) $ 5,992 Other comprehensive income before reclassifications 412 6,392 3,013 9,817 Amounts reclassified from accumulated other comprehensive income (loss) (1) 29 (8,913) — (8,884) Net current period other comprehensive income (loss) 441 (2,521) 3,013 933 June 30, 2023 $ (67) $ 22,151 $ (15,159) $ 6,925 (1) See the following table for details about these reclassifications. Amounts in parentheses indicate debits. The following table presents the reclassifications out of accumulated other comprehensive income (loss) for the three and six months ended June 30, 2024 and 2023, respectively: Details about Accumulated Other Comprehensive Income Components Amounts reclassified from Accumulated Other Comprehensive Loss (Income) (1) Affected line item where Three months ended Six months ended 2024 2023 2024 2023 Amortization of defined benefit and other postretirement items: Net loss $ 6 $ 29 $ 7 $ 28 Other (expense) income (2) Net prior service cost (credit) 7 (31) 15 (62) Other (expense) income (2) 13 (2) 22 (34) Total before tax (3) — (6) 5 Tax (expense) benefit $ 10 $ (2) $ 16 $ (29) Net of tax Gains and losses on cash flow hedges: Interest rate caps $ 4,662 $ 11,187 $ 9,318 $ 11,885 Interest income (expense) (1,166) (2,800) (2,329) (2,972) Tax expense $ 3,496 $ 8,387 $ 6,989 $ 8,913 Net of tax Total reclassifications for the period $ 3,506 $ 8,385 $ 7,005 $ 8,884 Net of tax (1) Amounts in parentheses indicate debits to profit/loss. (2) These accumulated other comprehensive income (loss) components are components of net periodic pension and other postretirement cost (see Note 14 to these condensed consolidated financial statements for additional details). Treasury Stock Repurchases 2022 Stock Repurchase Program On April 27, 2022, the Board approved a stock repurchase program that authorized the Company to purchase up to $450,000 of the Company’s common stock over the four-year period from the date of approval. Under the plan, the Company is permitted to repurchase shares from time to time for cash in open market transactions or in privately negotiated transactions with an equity sponsor in accordance with applicable federal securities laws, with the Company determining the timing and the amount of any repurchases based on its evaluation of market conditions, share price and other factors. During the six months ended June 30, 2024, the Company repurchased 552,081 shares on the open market at an average price of $9.05 per share, for a total of $4,998 , excluding brokerage commissions and accrued excise tax. As of June 30, 2024, $229,594 was available for share repurchases under the program. During the six months ended June 30, 2024, the Company did not accrue excise tax related to these repurchases, net of shares issued under the Company’s equity incentive program (see Note 18 to these condensed consolidated financial statements). During the six m onths ended June 30, 2023, in connection with secondary offerings of the Company’s common stock by an equity sponsor in March and May 2023, the Company repurchased 7,000,000 shares of its common stock sold in the offerings from the underwriters at a weighted average price of $10.48 per share concurrently with the closing of the offerings, for a total of $73,373 , excluding accrued excise tax . During the six months ended June 30, 2023 , the Company accrued excise tax of $630 related to these repurchases, net of shares issued under the Company’s equity incentive program. This amount was included in accrued liabilities in the condensed consolidated balance sheet and is treated by the Company as a cost of the treasury stock transactions in equity. Tax Withholdings on Equity Award Vesting In connection with the vesting of restricted stock awards (“RSA” or “RSAs”), restricted stock units (“RSU” or “RSUs”) and performance stock units (“PSU” or “PSUs”), shares of common stock may be delivered to the Company by employees to satisfy withholding tax obligations at the instruction of the employee award holders. These transactions, when they occur, are accounted for as stock repurchases by the Company, with the shares returned to treasury stock at a cost representing the payment by the Company of the tax obligations on behalf of the employees in lieu of shares for the vesting unit. There were 128,801 and 95,269 shares delivered to the Company to cover tax payments for the six months ended June 30, 2024 and 2023, respectively and the fair value of those shares withheld were $1,218 and $866 for the six months ended June 30, 2024 and 2023, respectively.

Goodwill

Goodwill	6 Months Ended
	Jun. 30, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	6. Goodwill: The change in the carrying amount of goodwill for the six months ended June 30, 2024 is summarized as follows: Ecoservices Advanced Materials & Catalysts Total Balance as of December 31, 2023 $ 326,589 $ 77,881 $ 404,470 Foreign exchange impact — (195) (195) Balance as of June 30, 2024 $ 326,589 $ 77,686 $ 404,275 The Company completes its annual goodwill and indefinite-lived intangible assets impairment test during the fourth quarter of each year, or more frequently if triggering events indicate a possible impairment. The Company determines the fair value of its reporting units using both a market approach and an income, or discounted cash flow, approach. As of October 1, 2023, the date of the Company’s most recent quantitative assessments, the fair values of each of the Company’s reporting units and the fair values of the Company’s indefinite-lived trade names and trademarks exceeded their respective carrying values. During the six months ended June 30, 2024, the Company did not identify any events or circumstances that would more likely than not reduce the fair value of the Company's reporting units below their respective carrying values. Although the estimated fair value of the Advanced Materials & Catalysts reporting unit exceeded its carrying value on October 1, 2023 by over 30%, the Company has experienced unfavorable effects on current operations resulting from certain macroeconomic and industry factors in specific end uses during the six months ended June 30, 2024. Prolonged unfavorable effects could adversely impact the estimated fair value of the Advanced Materials & Catalysts reporting unit in future periods and may result in impairment charges.

Other Operating Expense, Net

Other Operating Expense, Net	6 Months Ended
	Jun. 30, 2024
Other Income and Expenses [Abstract]
Other Operating Expense, Net	7. Other Operating Expense, Net: A summary of other operating expense, net is as follows: Three months ended Six months ended 2024 2023 2024 2023 Amortization expense $ 2,644 $ 2,643 $ 5,289 $ 5,280 Transaction and other related costs 140 1,190 198 2,624 Restructuring, integration and business optimization costs 159 1,106 385 2,129 Net (gain) loss on asset disposals (34) 1,128 614 2,306 Other, net 199 195 288 641 $ 3,108 $ 6,262 $ 6,774 $ 12,980

Inventories, Net

Inventories, Net	6 Months Ended
	Jun. 30, 2024
Inventory Disclosure [Abstract]
Inventories, Net	8. Inventories, Net: Inventories, net are classified and valued as follows: June 30, December 31, Finished products and work in process $ 48,536 $ 41,658 Raw materials 3,491 3,457 $ 52,027 $ 45,115 Valued at lower of cost or market: LIFO basis $ 30,003 $ 24,815 Valued at lower of cost and net realizable value: FIFO or average cost basis 22,024 20,300 $ 52,027 $ 45,115

Investments in Affiliated Compa

Investments in Affiliated Companies	6 Months Ended
	Jun. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Investments in Affiliated Companies	9. Investments in Affiliated Companies: The Company accounts for investments in affiliated companies under the equity method. Affiliated companies accounted for on the equity basis as of June 30, 2024 are as follows: Company Country Percent Zeolyst International USA 50% Zeolyst C.V. Netherlands 50% Following is summarized information of the combined investments (1) : Three months ended Six months ended 2024 2023 2024 2023 Sales $ 70,644 $ 99,188 $ 127,505 $ 155,085 Gross profit 16,751 34,461 33,929 44,571 Operating income 5,739 25,103 12,583 27,502 Net income 4,665 25,926 12,010 29,573 (1) Summarized information of the combined investments is presented at 100%; the Company’s share of the net assets and net income of affiliates is calculated based on the percent ownership specified in the table above. The Company’s investments in affiliated companies balance as of June 30, 2024 and December 31, 2023 includes net purchase accounting fair value adjustments of $222,073 and $224,614, respectively, related to a prior business combination, consisting primarily of goodwill and intangible assets such as customer relationships, technical know-how and trade names. Consolidated equity in net income from affiliates is net of $940 and $2,541 of amortization expense related to purchase accounting fair value adjustments for the three and six months ended June 30, 2024, respectively. Consolidated equity in net income from affiliates is net of $1,601 and $3,201 of amortization expense related to purchase accounting fair value adjustments for the three and six months ended June 30, 2023, respectively. The Company had receivables due from affiliates of $5,018 and $3,231 as of June 30, 2024 and December 31, 2023, respectively, which were included in prepaid and other current assets in the condensed consolidated balance sheets. The Company had payables from affiliates of $2,859 and $1,351 as of June 30, 2024 and December 31, 2023, which were included in accrued liabilities in the condensed consolidated balance sheets. Receivables and payables due from affiliates are generally non-trade. Sales to affiliates were $2,110 for the three and six months ended June 30, 2024, respectively and $757 and $2,457 for the three and six months ended June 30, 2023, respectively. There were no purchases from affiliates for the three and six months ended June 30, 2024 and 2023, respectively.

Property, Plant and Equipment

Property, Plant and Equipment	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	10. Property, Plant and Equipment: A summary of property, plant and equipment, at cost, and related accumulated depreciation is as follows: June 30, December 31, Land $ 96,807 $ 96,833 Buildings and improvements 92,085 84,860 Machinery and equipment 851,706 820,509 Construction in progress 35,620 42,000 1,076,218 1,044,202 Less: accumulated depreciation (502,659) (467,298) $ 573,559 $ 576,904 Depreciation expense was $18,108 and $36,523 for the three and six months ended June 30, 2024, respectively. Depreciation expense was $17,455 and $34,147 for the three and six months ended June 30, 2023, respectively.

Long-term Debt

Long-term Debt	6 Months Ended
	Jun. 30, 2024
Debt Disclosure [Abstract]
Long-term Debt	11. Long-term Debt: The summary of long-term debt is as follows: June 30, December 31, 2024 Term Loan Facility $ 873,000 $ 877,500 ABL Facility — — Total debt 873,000 877,500 Original issue discount (7,621) (6,162) Deferred financing costs (2,974) (3,392) Total debt, net of original issue discount and deferred financing costs 862,405 867,946 Less: current portion (6,548) (9,000) Total long-term debt, excluding current portion $ 855,857 $ 858,946 Term Loan Facility In June 2024, the Company amended its Term Loan Credit Agreement dated as of June 9, 2021 to, among other things, (a) reduce the interest rate applicable to all outstanding Secured Overnight Financing Rate (“SOFR”) term loans to term SOFR plus 2.25% per annum from a maximum of adjusted term SOFR plus 2.75% per annum, (b) reduce the interest rate applicable to all outstanding base rate term loans to the alternate base rate plus 1.25% per annum from a maximum of the alternate base rate plus 1.75% per annum and (c) extend the maturity date of all outstanding term loans to June 12, 2031 (the amended term loans, the “2024 Term Loan Facility”). As a result of the amendment, there is no longer a credit spread adjustment of 10 basis points. The Company evaluated the terms of the amendment in accordance with ASC 470-50 Debt - Modification and Extinguishment and determined that the amendment was primarily a modification of debt. As a result, the Company recorded $4,471 of third-party financing costs as debt extinguishment costs in the condensed consolidated income statement for the three and six months ended June 30, 2024 and capitalized $2,183 of original issued discount within long-term debt, excluding current portion on the condensed consolidated balance sheets as of June 30, 2024. In addition, previous unamortized deferred financing costs of $30 and original issue discount of $59 associated with the previously outstanding debt were written off as debt extinguishment costs for the three and six months ended June 30, 2024. The interest rate on the 2024 Term Loan Facility was 7.59% as of June 30, 2024. ABL Facility The borrowings under the senior secured asset-based lending revolving credit facility (“ABL Facility”) bears interest at a rate equal to an adjusted term SOFR, which includes a credit spread adjustment of 10 basis points or the base rate plus a margin of between 1.25% to 1.75% or 0.25% to 0.75%, respectively. The interest rate on the ABL Facility was 8.75% as of June 30, 2024. Fair Value of Debt The fair value of a financial instrument is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants. As of June 30, 2024 and December 31, 2023, the fair value of the Company’s term loan facility was $873,000 and $876,403, respectively. The fair value is classified as Level 2 based upon the fair value hierarchy (see Note 4 to these condensed consolidated financial statements for further information on fair value measurements).

Financial Instruments

Financial Instruments	6 Months Ended
	Jun. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments	12. Financial Instruments: The Company uses interest rate related derivative instruments to manage its exposure to changes in interest rates on its variable-rate debt instruments. The Company does not speculate using derivative instruments. By using derivative financial instruments to hedge exposures to changes in interest rates, the Company exposes itself to credit risk and market risk. Credit risk is the failure of the counterparty to perform under the terms of the derivative contract. When the fair value of a derivative contract is an asset, the counterparty owes the Company, which creates credit risk for the Company. When the fair value of a derivative contract is a liability, the Company owes the counterparty and therefore, the Company is not exposed to the counterparty’s credit risk in those circumstances. The Company minimizes counterparty credit risk in derivative instruments by entering into transactions with high quality counterparties. The derivative instruments entered into by the Company do not contain credit-risk-related contingent features. Market risk is the adverse effect on the value of a derivative instrument that results from a change in interest rates. The market risk associated with the Company’s derivative instruments is managed by establishing and monitoring parameters that limit the types and degree of market risk that may be undertaken. Use of Derivative Financial Instruments to Manage Interest Rate Risk. The Company is exposed to fluctuations in interest rates on its senior secured credit facilities. Changes in interest rates will not affect the market value of such debt but will affect the Company’s interest payments over the term of the loans. Likewise, an increase in interest rates could have a material impact on the Company’s condensed consolidated statements of cash flows. The Company hedges the interest rate fluctuations on debt obligations through interest rate cap agreements. The Company records these agreements at fair value as assets or liabilities in its condensed consolidated balance sheets. As the derivatives are designated and qualify as cash flow hedges, the gains or losses on the interest rate cap agreements are recorded in stockholders’ equity as a component of other comprehensive income, net of tax. Reclassifications of the gains and losses on the interest rate cap agreements into earnings are recorded as part of interest expense in the condensed consolidated statements of income as the Company makes its interest payments on the hedged portion of its senior secured credit facilities. Fair value is determined based on estimated amounts that would be received or paid to terminate the contracts at the reporting date based on quoted market prices. The following table provides a summary of the Company’s interest rate cap agreements: Financial instrument Number of instruments In effect as of June 30, 2024 Current notional amount of instruments in effect Annuitized premium of instruments in effect Interest rate cap 4 3 $ 650,000 $ 24,817 The current notional amounts of the three interest rate cap agreements in effect at June 30, 2024 are $250,000, $250,000 and $150,000. The Company entered into a $250,000 interest rate cap to mitigate interest rate volatility from August 2022 to October 2024, a $250,000 interest rate cap agreement to mitigate interest rate volatility from September 2023 to October 2025 and a $150,000 interest rate cap agreement to mitigate interest rate volatility from August 2023 to July 2024. The $150,000 interest rate cap agreement will increase to $175,000 to mitigate interest rate volatility from August 2024 to July 2026. The cap rate in effect at June 30, 2024 for all agreements in effect was 1.00%. The Company also entered into a forward starting interest rate cap agreement to mitigate interest volatility from November 2024 to October 2026. In February 2023, the Company amended all existing interest rate cap agreements to replace LIBOR with SOFR as the benchmark interest rate, with all other terms of the agreements remaining the same. This amendment changed the previously annuitized premiums on the existing interest rate cap agreements. The fair values of derivative instruments held as of June 30, 2024 and December 31, 2023, respectively are shown below: Balance sheet location June 30, December 31, Derivative assets Derivatives designated as cash flow hedges: Interest rate caps Prepaid and other current assets $ 12,270 $ 13,419 Interest rate caps Other long-term assets 7,695 5,602 Total derivative assets $ 19,965 $ 19,021 Derivative liabilities Derivatives designated as cash flow hedges: Interest rate caps Other long-term liabilities $ 403 $ 2,496 Total derivative liabilities $ 403 $ 2,496 The following table shows the effect of the Company’s derivative instruments designated as cash flow hedges on AOCI for the three and six months ended June 30, 2024 and 2023, respectively: Three months ended June 30, 2024 2023 Location of gain (loss) reclassified from AOCI into income Amount of gain (loss) recognized in OCI on derivatives Amount of gain (loss) reclassified from AOCI into income Amount of gain (loss) recognized in OCI on derivatives Amount of gain (loss) reclassified from AOCI into income Interest rate caps Interest (expense) income $ 3,229 $ (4,662) $ 18,246 $ 11,187 Six months ended June 30, 2024 2023 Location of gain (loss) reclassified from AOCI into income Amount of gain (loss) recognized in OCI on derivatives Amount of gain (loss) reclassified from AOCI into income Amount of gain (loss) recognized in OCI on derivatives Amount of gain (loss) reclassified from AOCI into income Interest rate caps Interest (expense) income $ 13,037 $ (9,318) $ 8,641 $ 11,885 The following table shows the effect of the Company’s cash flow hedge accounting on the condensed consolidated statements of income for the three and six months ended June 30, 2024 and 2023, respectively: Location and amount of gain (loss) recognized in income on cash flow hedging relationships Three months ended Six months ended 2024 2023 2024 2023 Total amounts of income and expense line items presented in the statement of income in which the effects of cash flow hedges are recorded in interest (expense) income $ (12,895) $ (9,168) $ (26,304) $ (19,000) The effects of cash flow hedging: Gain (loss) on cash flow hedging relationships: Interest contracts: Amount reclassified from AOCI into income 4,662 11,187 9,318 11,885 The amount of unrealized losses in AOCI related to the Company’s cash flow hedges that is expected to be reclassified to the condensed consolidated statement of income over the next twelve months is $8,700 as of June 30, 2024.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2024
Income Tax Disclosure [Abstract]
Income Taxes	13. Income Taxes: The effective income tax rate for the three months ended June 30, 2024 was 27.1%, compared to 25.2% for the three months ended June 30, 2023. The effective income tax rate for the six months ended June 30, 2024 was 30.9%, compared to 28.3% for the six months ended June 30, 2023. The Company’s effective income tax rates for the three and six months ended June 30, 2024 and 2023, respectively, fluctuated primarily due to the increased discrete tax impact relative to pre-tax book income related to a stock compensation shortfall and tax expense associated with the recording of accrued penalties and interest on historical uncertain tax positions. The difference between the U.S. federal statutory income tax rate and the Company’s effective income tax rate for the six months ended June 30, 2024 was mainly due to state and local taxes, a discrete shortfall tax expense related to stock compensation and a discrete tax expense associated with the recording of accrued penalties and interest on historical uncertain tax positions. The difference between the U.S. federal statutory income tax rate and the Company’s effective income tax rate for the six months ended June 30, 2023 was mainly due to state and local taxes, a discrete shortfall tax expense related to stock compensation, a discrete tax expense associated with the recording of accrued penalties and interest associated with historical uncertain tax positions, and a discrete tax benefit connected to state and local tax law changes.

Benefit Plans

Benefit Plans	6 Months Ended
	Jun. 30, 2024
Retirement Benefits [Abstract]
Benefit Plans	14. Benefit Plans: The following tables present the components of net periodic (benefit) expense for the Company-sponsored defined benefit pension and postretirement plans, which cover certain employees and retirees located in the U.S. Defined Benefit Pension Plans Three months ended Six months ended 2024 2023 2024 2023 Interest cost $ 808 $ 871 $ 1,616 $ 1,742 Expected return on plan assets (827) (837) (1,654) (1,674) Settlement (gain) loss (6) 29 (6) 29 Net periodic (benefit) expense $ (25) $ 63 $ (44) $ 97 Other Postretirement Benefit Plan Three months ended Six months ended 2024 2023 2024 2023 Interest cost $ 6 $ 6 $ 12 $ 12 Amortization of prior service credit (7) (31) (15) (62) Amortization of net gain — — (1) (1) Net periodic benefit $ (1) $ (25) $ (4) $ (51) All components of net periodic (benefit) expense other than service cost are presented within other expense (income), net in the Company’s condensed consolidated statements of income.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	6 Months Ended
	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	15. Commitments and Contingent Liabilities: There is a risk of environmental impact in the Company’s manufacturing operations. The Company’s environmental policies and practices are designed to comply with existing laws and regulations and to minimize the possibility of significant environmental impact. The Company is also subject to various other lawsuits and claims with respect to matters such as governmental regulations, labor and other actions arising out of the normal course of business. All claims that are probable and reasonably estimable have been accrued for in the Company’s condensed consolidated financial statements. When these matters are ultimately concluded and determined, the Company believes that there will be no material adverse effect on its consolidated financial position, results of operations or liquidity.

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2024
Related Party Transactions [Abstract]
Related Party Transactions	16. Related Party Transactions: The Company maintains certain policies and procedures for the review, approval and ratification of related party transactions to ensure that all transactions with selected parties are fair, reasonable and in the Company’s best interests. All significant relationships and transactions are separately identified by management if they meet the definition of a related party or a related party transaction. Related party transactions include transactions that occurred during the year, or are currently proposed, in which the Company was or will be a participant, and for which any related person had or will have a direct or indirect material interest. All related party transactions are reviewed, approved and documented by the appropriate level of the Company’s management in accordance with these policies and procedures. Joint Venture Agreement The Company entered into a joint venture agreement (the “ZI Partnership Agreement”) in 1988 with Shell Catalysts & Technologies, an affiliate of Royal Dutch Shell plc, to form Zeolyst International, a 50/50 joint venture partnership (the “Partnership”). Under the terms of the ZI Partnership Agreement, the Partnership leases certain land used in its Kansas City production facilities from Ecovyst. This lease, which has been recorded as an operating lease, provided for rental payments to the Company of $78 and $155 for the three and six months ended June 30, 2024 and 2023, respectively. The terms of this lease are evergreen as long as the ZI Partnership Agreement is in place. The Partnership had no sales to the Company for the three and six months ended June 30, 2024 and 2023, respectively. The Partnership purchases certain raw materials from the Company and was charged for various manufacturing costs incurred at the Company’s Kansas City production facility. The amount of these costs charged to the Partnership were $6,050 and $10,084 for the three and six months ended June 30, 2024, respectively and $5,028 and $10,869 for the three and six months ended June 30, 2023, respectively. Certain administrative, marketing, engineering, management-related and research and development services are provided to the Partnership by the Company. The Partnership was charged $4,600 and $8,900 for the three and six months ended June 30, 2024 and $3,618 and $7,252 for the three and six months ended June 30, 2023, respectively, for these services. In addition, the Partnership was charged certain product demonstration costs of $238 and $595 for the three and six months ended June 30, 2024, respectively and $428 and $928 for the three and six months ended June 30, 2023, respectively. These charges to the Partnership are recorded as reductions in either cost of goods sold or selling, general and administrative expenses in the consolidated statements of income, depending on the nature of the expenditures. The Company had an accounts receivable from the Partnership of $5,008 and $3,164 as of June 30, 2024 and December 31, 2023, respectively. There were no accounts payable with the Partnership as of June 30, 2024 and December 31, 2023, respectively.

Reportable Segments

Reportable Segments	6 Months Ended
	Jun. 30, 2024
Segment Reporting [Abstract]
Reportable Segments	17. Reportable Segments: Summarized financial information for the Company’s reportable segments is shown in the following table: Three months ended Six months ended 2024 2023 2024 2023 Sales: Ecoservices $ 153,958 $ 158,065 $ 295,560 $ 295,805 Advanced Materials & Catalysts (1) 28,862 26,045 47,797 49,179 Total $ 182,820 $ 184,110 $ 343,357 $ 344,984 Adjusted EBITDA: (2) Ecoservices $ 49,709 $ 60,136 $ 91,203 $ 96,924 Advanced Materials & Catalysts (3) 14,717 25,371 25,846 38,359 Adjusted EBITDA from reportable segments $ 64,426 $ 85,507 $ 117,049 $ 135,283 (1) Excludes the Company’s proportionate share of sales from the Zeolyst Joint Venture accounted for using the equity method (see Note 9 to these condensed consolidated financial statements for further information). The proportionate share of sales excluded is $29,024 and $52,505 for the three and six months ended June 30, 2024, respectively. The proportionate share of sales excluded is $44,689 and $66,763 for the three and six months ended June 30, 2023, respectively. (2) The Company defines Adjusted EBITDA as EBITDA adjusted for certain items as noted in the reconciliation below. Management evaluates the performance of its segments and allocates resources based on several factors, of which the primary measure is Adjusted EBITDA. Adjusted EBITDA should not be considered as an alternative to net income as an indicator of the Company’s operating performance. Adjusted EBITDA as defined by the Company may not be comparable with EBITDA or Adjusted EBITDA as defined by other companies. (3) The Adjusted EBITDA for the Company’s Advanced Materials & Catalysts segment includes the Company’s 50% portion of the Adjusted EBITDA from the Zeolyst Joint Venture. For the three months ended June 30, 2024, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $5,559, which includes $1,392 of equity in net income plus $940 of amortization of investment in affiliate step-up and $3,227 of joint venture depreciation, amortization and interest. For the six months ended June 30, 2024, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $12,486, which includes $3,464 of equity in net income plus $2,541 of amortization of investment in affiliate step-up and $6,481 of joint venture depreciation, amortization and interest. For the three months ended June 30, 2023, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $16,194, which includes $11,382 of equity in net income plus $1,601 of amortization of investment in affiliate step-up and $3,212 of joint venture depreciation, amortization and interest. For the six months ended June 30, 2023, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $21,630, which includes $11,608 of equity in net income plus $3,201 of amortization of investment in affiliate step-up and $6,821 of joint venture depreciation, amortization and interest. A reconciliation of income before income taxes to Adjusted EBITDA is as follows: Three months ended Six months ended 2024 2023 2024 2023 Reconciliation of income before income taxes to Adjusted EBITDA from reportable segments Income before income taxes $ 11,375 $ 34,909 $ 13,775 $ 34,385 Interest expense, net 12,895 9,168 26,304 19,000 Depreciation and amortization 21,624 20,969 43,557 41,166 Unallocated corporate expenses 7,532 6,153 14,613 13,080 Joint venture depreciation, amortization and interest 3,227 3,212 6,481 6,821 Amortization of investment in affiliate step-up 940 1,601 2,541 3,201 Debt extinguishment costs 4,560 — 4,560 — Net (gain) loss on asset disposals (34) 1,128 614 2,306 Foreign exchange (gain) loss (99) (398) 79 (1,136) LIFO (benefit) expense (1,547) 1,111 (2,671) 2,510 Transaction and other related costs 140 1,190 198 2,624 Equity-based compensation 3,827 5,002 7,507 9,070 Restructuring, integration and business optimization expenses 159 1,106 385 2,129 Other (173) 356 (894) 127 Adjusted EBITDA from reportable segments $ 64,426 $ 85,507 $ 117,049 $ 135,283

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	18. Stock-Based Compensation: The Company has an equity incentive plan under which it grants common stock awards to employees, directors and affiliates of the Company. At June 30, 2024, 8,032,299 shares of common stock were available for issuance under the plan. The Company historically has settled these awards through the issuance of new shares. RSU During the six months ended June 30, 2024, the Company granted 1,126,166 RSUs under its equity incentive plan. Each RSU provides the recipient with the right to receive a share of common stock subject to graded vesting terms based on service, which for the awards granted during the six months ended June 30, 2024, generally requires approximately one year of service for members of the Company’s board of directors and approximately three years of service for employees. The value of the RSUs granted during the six months ended June 30, 2024 was based on the average of the high and low trading prices of the Company’s common stock on the NYSE on the preceding trading day, in accordance with the Company’s policy for valuing such awards. Compensation expense related to the RSUs is recognized on a straight-line basis over the respective vesting period. PSU 2024 Grants During the six months ended June 30, 2024, the Company granted 535,629 PSUs (at target) under its equity incentive plan. The PSUs granted during the six months ended June 30, 2024 provide the recipients with the right to receive shares of common stock dependent on 50% of a Company-specific financial performance target and 50% on the relative increase in the total shareholder return (“TSR”) goal (“the Performance measures”). The Performance measures are measured independently of each other, but achievement of both metrics is measured on the same three-year performance period from January 1, 2024 through December 31, 2026 (“Performance period”). Depending on the Company’s performance relative to the Performance measures, each PSU award recipient is eligible to receive a percentage of the target number of shares granted to the recipient, ranging from 50% to 200%. The PSUs, to the extent earned, will vest on the date the Compensation Committee of the Company’s Board of Directors (“Compensation Committee”) certifies the achievement of the Performance measures for the Performance period, which will occur subsequent to the end of the Performance period and after the Company files its annual consolidated financial statements for the year ending December 31, 2026. Achievement of the Company-specific financial performance target is measured based on the actual three-year cumulative results across the Performance period. The TSR goal is based on the Company’s actual TSR performance against companies in the S&P 1500 Specialty Chemicals Index over the Performance period. The TSR goal, which determines how much of the 50% of the PSUs granted during 2024 may be earned, is considered a market condition as opposed to a vesting condition. Because a market condition is not considered a vesting condition, it is reflected in the grant date fair value of the award and the associated compensation cost based on the fair value of the award is recognized over the Performance period, regardless of whether the Company actually achieves the market condition or the level of achievement, as long as service is provided by the recipient. The Company used a Monte Carlo simulation to estimate the $11.64 weighted average fair value of the awards granted subject to the TSR goal during the six months ended June 30, 2024, with the following weighted average assumptions: Expected dividend yield — % Risk-free interest rate 4.09 % Expected volatility 39.45 % Expected term (in years) 2.95 2021 Grants In February 2024, the Compensation Committee certified the achievement of the performance metrics for the three-year period ended December 31, 2023, related to the PSUs granted during the year ended December 31, 2021. The PSUs granted during the year ended December 31, 2021 provide the recipients with the right to receive shares of common stock dependent on the achievement of a TSR goal, and are generally subject to the provision of service through the vesting date of the award. The TSR goal was based on the Company’s actual TSR percentage increase over the performance period. The awards vested during the six months ended June 30, 2024 with no percentage of the TSR goal earned. Award Activity The following table summarizes the activity for the Company’s RSUs and PSUs for the six months ended June 30, 2024: Restricted Stock Units Performance Stock Units Number of Weighted average grant date fair value (per share) Number of Weighted average grant date fair value (per share) Nonvested as of December 31, 2023 1,962,828 $ 10.55 959,217 (1) $ 11.84 Granted 1,126,166 $ 8.84 535,629 $ 10.23 Vested (999,788) $ 11.10 — $ — Forfeited (21,597) $ 10.19 (126,497) $ 12.99 Nonvested as of June 30, 2024 2,067,609 $ 9.36 1,368,349 (1) $ 11.10 (1) Based on target. During the six months ended June 30, 2024, the Company also granted 4,540 of RSAs with a weighted average grant date fair value of $8.81 per share that immediately vested. Cash proceeds received by the Company from the exercise of stock options were not material for the six months ended June 30, 2024. Stock-Based Compensation Expense For the three months ended June 30, 2024 and 2023, stock-based compensation expense for the Company was $3,827 and $5,002, respectively. The associated income tax benefit based on the applicable statutory rate recognized in the condensed consolidated statements of income for the three months ended June 30, 2024 and 2023 was $939 and $1,181, respectively. For the six months ended June 30, 2024 and 2023, stock-based compensation expense for the Company was $7,507 and $9,070, respectively. The associated income tax benefit based on the applicable statutory rate recognized in the condensed consolidated statements of income for the six months ended June 30, 2024 and 2023 was $1,841 and $2,154, respectively. As of June 30, 2024, unrecognized compensation cost was $14,391 for RSUs and $9,474 for PSUs considered probable of vesting, and the weighted-average period over which these costs are expected to be recognized at June 30, 2024 was 1.84 years for the RSUs and 2.13 years for the PSUs.

Earnings per Share

Earnings per Share	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Earnings per Share	19. Earnings per Share: Basic earnings per share is calculated as income available to common stockholders, divided by the weighted average number of common shares outstanding during the period. The weighted average number of common shares outstanding during the period for the computation of basic earnings per share excludes RSAs that have legally been issued but are nonvested during the period, as the sale of these shares is prohibited pending satisfaction of certain vesting conditions by the award recipients in order to earn the rights to the shares. Diluted earnings per share is calculated as income available to common stockholders, divided by the weighted average number of common and potential common shares outstanding during the period, if dilutive. Potential common shares reflect (1) unvested RSAs and RSUs with service vesting conditions, (2) PSUs with vesting conditions considered probable of achievement and (3) options to purchase common stock, all of which have been included in the diluted earnings per share calculation using the treasury stock method. The reconciliation from basic to diluted weighted average shares outstanding is as follows: Three months ended Six months ended 2024 2023 2024 2023 Weighted average shares outstanding – Basic 116,912,332 118,651,402 116,935,708 120,335,414 Dilutive effect of unvested common shares and RSUs with service conditions, PSUs considered probable of vesting and assumed stock option exercises and conversions 722,957 1,269,340 609,532 1,496,528 Weighted average shares outstanding – Diluted 117,635,289 119,920,742 117,545,240 121,831,942 Basic and diluted income per share are calculated as follows: Three months ended Six months ended 2024 2023 2024 2023 Numerator: Net income $ 8,295 $ 26,122 $ 9,516 $ 24,651 Denominator: Weighted average shares outstanding – Basic 116,912,332 118,651,402 116,935,708 120,335,414 Weighted average shares outstanding – Diluted 117,635,289 119,920,742 117,545,240 121,831,942 Net income per share: Basic income per share $ 0.07 $ 0.22 $ 0.08 $ 0.20 Diluted income per share $ 0.07 $ 0.22 $ 0.08 $ 0.20 The table below presents the details of the Company’s weighted average equity-based awards outstanding during each respective period that were excluded from the calculation of diluted earnings per share: Three months ended Six months ended 2024 2023 2024 2023 RSAs with performance only targets not achieved — — — 99,495 Stock options with performance only targets not achieved — — — 103,907 Anti-dilutive RSUs and PSUs 431,837 685,656 481,281 630,668 Anti-dilutive stock options 367,100 520,757 367,100 607,783 RSAs and stock options with performance only vesting conditions were not included in the dilution calculation, as the performance targets have not been achieved nor were probable of achievement as of the end of the respective periods. These awards and stock options were canceled on March 7, 2023 (see Note 18 to these condensed consolidated financial statements for additional information). Certain stock options to purchase shares of common stock were excluded from the computation of diluted earnings per share for the respective periods because the options’ exercise price was greater than the average market price of the common shares. These stock options and anti-dilutive awards are not included in the dilution calculation, as their inclusion would have the effect of increasing diluted income per share or reducing diluted loss per share.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	6 Months Ended
	Jun. 30, 2024
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	20. Supplemental Cash Flow Information: The following table presents supplemental cash flow information for the Company: Six months ended 2024 2023 Cash paid during the period for: Income taxes, net of refunds $ 16,439 $ 9,955 Interest (1) 33,155 19,391 Non-cash investing activity: Capital expenditures acquired on account but unpaid as of the period end 784 605 Non-cash financing activity: Accrued excise tax on share repurchases (Note 5) — 630 Right-of-use assets obtained in exchange for new lease liabilities (non-cash): Operating leases 2,957 6,202 (1) Cash paid for interest is shown net of capitalized interest and includes the cash received or paid on the Company’s interest rate cap agreements designated as cash flow hedges for the periods presented (see Note 12 to these condensed consolidated financial statements for details).

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2024
Subsequent Events [Abstract]
Subsequent Events	21. Subsequent Events: On July 24, 2024, the Company completed an equity investment in Pajarito Powder LLC, an innovative materials science company that focuses on supports and catalysts required for the manufacture and operation of electrolyzers and fuel cells, for $4,500 . Other than the above, the Company has evaluated subsequent events since the balance sheet date and determined that there are no additional items to disclose.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Net income	$ 8,295	$ 1,221	$ 26,122	$ (1,471)	$ 9,516	$ 24,651

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Jun. 30, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Background and Basis of Prese_2

Background and Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The condensed consolidated financial statements included herein are unaudited. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) have been condensed or omitted pursuant to such rules and regulations for interim reporting. In the opinion of management, all adjustments of a normal and recurring nature necessary to state fairly the financial position and results of operations have been included. The results of operations are not necessarily indicative of the expected results for the full year. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023.
Accounting Standards Not Yet Adopted	Accounting Standards Not Yet Adopted In November 2023, the Financial Accounting Standards Board (“FASB”) issued guidance to improve the disclosures related to public business entities reportable segments. This new guidance requires entities to provide information regarding significant segment expenses, especially those segment expenses that are regularly reported to the Company’s chief operating decision maker (the Company’s Chief Executive Officer), or CODM. The guidance also require public entities to disclose the nature, type and amounts of other segment items by reportable segment. Public business entities will also have to report all annual disclosures about segments profits or losses that are required by ASC 280 on an interim basis, including the significant segment expenses and other segment items. The new guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The disclosure will be implemented as required for the fiscal year ended December 31, 2024. The Company is currently evaluating the impact of this guidance. In December 2023, FASB issued guidance to improve disclosures related to incomes taxes. This new guidance requires public business entities to disaggregate information on the effective tax rate reconciliation and income taxes paid to provide greater transparency. Public business entities will be required to provide additional information in specified categories related to effective tax rate reconciliation in tabular form and provide income taxes paid by jurisdictions, with further disaggregation needed if amounts exceed 5% of the total. The new guidance is effective for fiscal years beginning after December 15, 2024. The disclosure will be implemented as required for the fiscal year ended December 31, 2025. The Company is currently evaluating the impact of this guidance. In October 2023, FASB issued guidance to amend either presentation or disclosure requirements related to fourteen subtopics in the FASB Accounting Standards Codification, that are currently in the SEC Regulation S-X or Regulation S-K. The new guidance was issued in response to the SEC’s ruling on disclosure simplification. For entities subject to existing SEC disclosure requirements, the effective date of each amendment of the topics will be the date that the SEC removes the related disclosure from Regulation S-X or Regulation S-K. The guidance must be applied prospectively, with no early adoption permitted for entities subject to those existing SEC disclosures. The Company is currently evaluating the impact of the new guidance as it pertains to the fourteen subtopics that would impact the business and will apply prospectively once in effect. In August 2023, the FASB issued guidance for entities that meet the definition of a joint venture or a corporate joint venture, to adopt a new basis of accounting upon the formation of the joint venture. The new guidance requires the initial measurement of contributed net assets and liabilities at fair value on the formation date, recognition of goodwill for the difference between the fair value of the joint venture’s equity and net assets, and disclosures about the nature and financial impact of the transaction. The new guidance requires prospective application and is effective for all joint ventures that are formed on or after January 1, 2025, with early adoption permitted. Joint ventures that formed before January 1, 2025 may elect to retrospectively apply the new guidance. The Company will apply the guidance to any new joint ventures formed after the effective date.
Derivative contracts	Derivative contracts Derivative assets and liabilities can be exchange-traded or traded over-the-counter (“OTC”). The Company generally values exchange-traded derivatives using models that calibrate to market transactions and eliminate timing differences between the closing price of the exchange-traded derivatives and their underlying instruments. OTC derivatives are valued using market transactions and other market evidence whenever possible, including market-based inputs to models, model calibration to market transactions, broker or dealer quotations or alternative pricing sources with reasonable levels of price transparency. When models are used, the selection of a particular model to value an OTC derivative depends on the contractual terms of, and specific risks inherent in, the instrument as well as the availability of pricing information in the market. The Company generally uses similar models to value similar instruments. Valuation models require a variety of inputs, including contractual terms, market prices and rates, forward curves, measures of volatility, and correlations of such inputs. For OTC derivatives that trade in liquid markets, such as forward contracts, swaps and options, model inputs can generally be corroborated by observable market data by correlation or other means, and model selection does not involve significant management judgment. As of June 30, 2024, th e Company had interest rate c aps th at were fair valued using Level 2 inputs. In addition, the Company applies a credit valuation adjustment to reflect credit risk which is calculated based on credit default swaps. To the extent that the Company’s net exposure under a specific master agreement is an asset, the Company utilizes the counterparty’s default swap rate. If the net exposure under a specific master agreement is a liability, the Company utilizes a default swap rate comparable to Ecovyst. The credit valuation adjustment is added to the discounted fair value to reflect the exit price that a market participant would be willing to receive to assume the Company’s liabilities or that a market participant would be willing to pay for the Company’s assets.

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	6 Months Ended
	Jun. 30, 2024
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The Company’s portfolio of products is integrated into a variety of end uses, which are described in the table below. Key End Uses Key Products Clean fuels, emission control & other • Refining hydrocracking catalysts • Emission control catalysts • Catalyst supports used in production of sustainable fuels such as renewable diesel • Catalysts used in production of sustainable aviation fuels • Catalyst activation • Aluminum sulfate solution • Ammonium bisulfite solution Polyethylene, polymers & engineered plastics • Catalysts for high-density polyethylene and chemicals syntheses • Antiblock for film packaging • Catalyst for advanced recycling Regeneration and treatment services • Sulfuric acid regeneration services • Treatment services Industrial, mining & automotive • Virgin sulfuric acid for mining • Virgin sulfuric derivatives for industrial production • Virgin sulfuric derivatives for nylon production The following tables disaggregate the Company’s sales, by segment and end uses, for the three and six months ended June 30, 2024 and 2023, respectively: Three months ended June 30, 2024 Ecoservices Advanced Materials & Catalysts (2) Total Clean fuels, emission control & other $ 8,614 $ — $ 8,614 Polyethylene, polymers & engineered plastics — 28,862 28,862 Regeneration and treatment services (1) 95,365 — 95,365 Industrial, mining & automotive 49,979 — 49,979 Total segment sales $ 153,958 $ 28,862 $ 182,820 Three months ended June 30, 2023 Ecoservices Advanced Materials & Catalysts (2) Total Clean fuels, emission control & other $ 8,426 $ — $ 8,426 Polyethylene, polymers & engineered plastics — 26,045 26,045 Regeneration and treatment services (1) 98,494 — 98,494 Industrial, mining & automotive 51,145 — 51,145 Total segment sales $ 158,065 $ 26,045 $ 184,110 Six months ended June 30, 2024 Ecoservices Advanced Materials & Catalyst (2) Total Clean fuels, emission control & other $ 16,003 $ — $ 16,003 Polyethylene, polymers & engineered plastics — 47,797 47,797 Regeneration and treatment services (1) 178,684 — 178,684 Industrial, mining & automotive 100,873 — 100,873 Total segment sales $ 295,560 $ 47,797 $ 343,357 Six months ended June 30, 2023 Ecoservices Advanced Materials & Catalyst (2) Total Clean fuels, emission control & other $ 13,166 $ — $ 13,166 Polyethylene, polymers & engineered plastics — 49,179 49,179 Regeneration and treatment services (1) 186,838 — 186,838 Industrial, mining & automotive 95,801 — 95,801 Total segment sales $ 295,805 $ 49,179 $ 344,984 (1) As described in Note 1 to these condensed consolidated financial statements, the Company experiences seasonal s ales fluctuations to customers in the regeneration services product group. (2) Excludes the Company’s proportionate share of sales from the Zeolyst International and Zeolyst C.V. joint ventures (collectively, the “Zeolyst Joint Venture”) accounted for using the equity method (see Note 9 to these condensed consolidated financial statements for further information).

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measured on Recurring Basis	The following tables present information about the Company’s assets and liabilities that were measured at fair value on a recurring basis as of June 30, 2024 and December 31, 2023, and indicates the fair value hierarchy of the valuation techniques the Company utilized to determine such fair value. June 30, Quoted Prices in Significant Other Significant Derivative assets: Interest rate caps (Note 12) $ 19,965 $ — $ 19,965 $ — Derivative liabilities: Interest rate caps (Note 12) $ 403 $ — $ 403 $ — December 31, Quoted Prices in Significant Other Significant Derivative assets: Interest rate caps (Note 12) $ 19,021 $ — $ 19,021 $ — Derivative liabilities: Interest rate caps (Note 12) $ 2,496 $ — $ 2,496 $ —

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2024
Equity [Abstract]
Pre-tax and After-tax Components of Other Comprehensive Income (Loss)	The following tables present the tax effects of each component of other comprehensive income (loss) for the three and six months ended June 30, 2024 and 2023, respectively: Three months ended June 30, 2024 2023 Pre-tax Tax benefit/ After-tax amount Pre-tax Tax benefit/ After-tax amount Defined benefit and other postretirement plans: Net gain $ 714 $ (178) $ 536 $ 651 $ (162) $ 489 Net prior service cost (7) 1 (6) (31) 7 (24) Benefit plans, net 707 (177) 530 620 (155) 465 Net (loss) gain from hedging activities (1,433) 358 (1,075) 7,059 (1,660) 5,399 Foreign currency translation (679) — (679) 828 — 828 Other comprehensive income (loss) $ (1,405) $ 181 $ (1,224) $ 8,507 $ (1,815) $ 6,692 Six months ended June 30, 2024 2023 Pre-tax Tax benefit/ After-tax amount Pre-tax Tax benefit/ After-tax amount Defined benefit and other postretirement plans: Net gain $ 713 $ (178) $ 535 $ 650 $ (162) $ 488 Net prior service cost (15) 4 (11) (62) 15 (47) Benefit plans, net 698 (174) 524 588 (147) 441 Net gain (loss) from hedging activities 3,719 (930) 2,789 (3,244) 723 (2,521) Foreign currency translation (2,363) — (2,363) 3,013 — 3,013 Other comprehensive income $ 2,054 $ (1,104) $ 950 $ 357 $ 576 $ 933 The following tables present the changes in accumulated other comprehensive income (loss), net of tax, by component for the six months ended June 30, 2024 and 2023, respectively: Defined benefit Net gain (loss) Foreign Total December 31, 2023 $ 612 $ 12,546 $ (14,116) $ (958) Other comprehensive income (loss) before reclassifications 540 9,778 (2,363) 7,955 Amounts reclassified from accumulated other comprehensive loss (1) (16) (6,989) — (7,005) Net current period other comprehensive income (loss) 524 2,789 (2,363) 950 June 30, 2024 $ 1,136 $ 15,335 $ (16,479) $ (8) December 31, 2022 $ (508) $ 24,672 $ (18,172) $ 5,992 Other comprehensive income before reclassifications 412 6,392 3,013 9,817 Amounts reclassified from accumulated other comprehensive income (loss) (1) 29 (8,913) — (8,884) Net current period other comprehensive income (loss) 441 (2,521) 3,013 933 June 30, 2023 $ (67) $ 22,151 $ (15,159) $ 6,925 (1) See the following table for details about these reclassifications. Amounts in parentheses indicate debits.
Reclassifications out of Accumulated Other Comprehensive Income	The following table presents the reclassifications out of accumulated other comprehensive income (loss) for the three and six months ended June 30, 2024 and 2023, respectively: Details about Accumulated Other Comprehensive Income Components Amounts reclassified from Accumulated Other Comprehensive Loss (Income) (1) Affected line item where Three months ended Six months ended 2024 2023 2024 2023 Amortization of defined benefit and other postretirement items: Net loss $ 6 $ 29 $ 7 $ 28 Other (expense) income (2) Net prior service cost (credit) 7 (31) 15 (62) Other (expense) income (2) 13 (2) 22 (34) Total before tax (3) — (6) 5 Tax (expense) benefit $ 10 $ (2) $ 16 $ (29) Net of tax Gains and losses on cash flow hedges: Interest rate caps $ 4,662 $ 11,187 $ 9,318 $ 11,885 Interest income (expense) (1,166) (2,800) (2,329) (2,972) Tax expense $ 3,496 $ 8,387 $ 6,989 $ 8,913 Net of tax Total reclassifications for the period $ 3,506 $ 8,385 $ 7,005 $ 8,884 Net of tax (1) Amounts in parentheses indicate debits to profit/loss. (2) These accumulated other comprehensive income (loss) components are components of net periodic pension and other postretirement cost (see Note 14 to these condensed consolidated financial statements for additional details).

Goodwill (Tables)

Goodwill (Tables)	6 Months Ended
	Jun. 30, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Change in Carrying Amount of Goodwill	The change in the carrying amount of goodwill for the six months ended June 30, 2024 is summarized as follows: Ecoservices Advanced Materials & Catalysts Total Balance as of December 31, 2023 $ 326,589 $ 77,881 $ 404,470 Foreign exchange impact — (195) (195) Balance as of June 30, 2024 $ 326,589 $ 77,686 $ 404,275

Other Operating Expense, Net (T

Other Operating Expense, Net (Tables)	6 Months Ended
	Jun. 30, 2024
Other Income and Expenses [Abstract]
Summary of Other Operating Expense, Net	A summary of other operating expense, net is as follows: Three months ended Six months ended 2024 2023 2024 2023 Amortization expense $ 2,644 $ 2,643 $ 5,289 $ 5,280 Transaction and other related costs 140 1,190 198 2,624 Restructuring, integration and business optimization costs 159 1,106 385 2,129 Net (gain) loss on asset disposals (34) 1,128 614 2,306 Other, net 199 195 288 641 $ 3,108 $ 6,262 $ 6,774 $ 12,980

Inventories, Net (Tables)

Inventories, Net (Tables)	6 Months Ended
	Jun. 30, 2024
Inventory Disclosure [Abstract]
Inventories, Net	Inventories, net are classified and valued as follows: June 30, December 31, Finished products and work in process $ 48,536 $ 41,658 Raw materials 3,491 3,457 $ 52,027 $ 45,115 Valued at lower of cost or market: LIFO basis $ 30,003 $ 24,815 Valued at lower of cost and net realizable value: FIFO or average cost basis 22,024 20,300 $ 52,027 $ 45,115

Investments in Affiliated Com_2

Investments in Affiliated Companies (Tables)	6 Months Ended
	Jun. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Ownership Percentage and Summarized Income Statement	Affiliated companies accounted for on the equity basis as of June 30, 2024 are as follows: Company Country Percent Zeolyst International USA 50% Zeolyst C.V. Netherlands 50% Following is summarized information of the combined investments (1) : Three months ended Six months ended 2024 2023 2024 2023 Sales $ 70,644 $ 99,188 $ 127,505 $ 155,085 Gross profit 16,751 34,461 33,929 44,571 Operating income 5,739 25,103 12,583 27,502 Net income 4,665 25,926 12,010 29,573 (1) Summarized information of the combined investments is presented at 100%; the Company’s share of the net assets and net income of affiliates is calculated based on the percent ownership specified in the table above.

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Summary of Property, Plant and Equipment	A summary of property, plant and equipment, at cost, and related accumulated depreciation is as follows: June 30, December 31, Land $ 96,807 $ 96,833 Buildings and improvements 92,085 84,860 Machinery and equipment 851,706 820,509 Construction in progress 35,620 42,000 1,076,218 1,044,202 Less: accumulated depreciation (502,659) (467,298) $ 573,559 $ 576,904

Long-term Debt (Tables)

Long-term Debt (Tables)	6 Months Ended
	Jun. 30, 2024
Debt Disclosure [Abstract]
Summary of Long-Term Debt	The summary of long-term debt is as follows: June 30, December 31, 2024 Term Loan Facility $ 873,000 $ 877,500 ABL Facility — — Total debt 873,000 877,500 Original issue discount (7,621) (6,162) Deferred financing costs (2,974) (3,392) Total debt, net of original issue discount and deferred financing costs 862,405 867,946 Less: current portion (6,548) (9,000) Total long-term debt, excluding current portion $ 855,857 $ 858,946

Financial Instruments (Tables)

Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Interest Rate Cap Agreements	The following table provides a summary of the Company’s interest rate cap agreements: Financial instrument Number of instruments In effect as of June 30, 2024 Current notional amount of instruments in effect Annuitized premium of instruments in effect Interest rate cap 4 3 $ 650,000 $ 24,817
Fair Values of Derivative Instruments Held	The fair values of derivative instruments held as of June 30, 2024 and December 31, 2023, respectively are shown below: Balance sheet location June 30, December 31, Derivative assets Derivatives designated as cash flow hedges: Interest rate caps Prepaid and other current assets $ 12,270 $ 13,419 Interest rate caps Other long-term assets 7,695 5,602 Total derivative assets $ 19,965 $ 19,021 Derivative liabilities Derivatives designated as cash flow hedges: Interest rate caps Other long-term liabilities $ 403 $ 2,496 Total derivative liabilities $ 403 $ 2,496
Effect of Derivative Instruments Designated as Hedges on Other Comprehensive Income	The following table shows the effect of the Company’s derivative instruments designated as cash flow hedges on AOCI for the three and six months ended June 30, 2024 and 2023, respectively: Three months ended June 30, 2024 2023 Location of gain (loss) reclassified from AOCI into income Amount of gain (loss) recognized in OCI on derivatives Amount of gain (loss) reclassified from AOCI into income Amount of gain (loss) recognized in OCI on derivatives Amount of gain (loss) reclassified from AOCI into income Interest rate caps Interest (expense) income $ 3,229 $ (4,662) $ 18,246 $ 11,187 Six months ended June 30, 2024 2023 Location of gain (loss) reclassified from AOCI into income Amount of gain (loss) recognized in OCI on derivatives Amount of gain (loss) reclassified from AOCI into income Amount of gain (loss) recognized in OCI on derivatives Amount of gain (loss) reclassified from AOCI into income Interest rate caps Interest (expense) income $ 13,037 $ (9,318) $ 8,641 $ 11,885
Cash Flow Hedge Impact on Income Statement	The following table shows the effect of the Company’s cash flow hedge accounting on the condensed consolidated statements of income for the three and six months ended June 30, 2024 and 2023, respectively: Location and amount of gain (loss) recognized in income on cash flow hedging relationships Three months ended Six months ended 2024 2023 2024 2023 Total amounts of income and expense line items presented in the statement of income in which the effects of cash flow hedges are recorded in interest (expense) income $ (12,895) $ (9,168) $ (26,304) $ (19,000) The effects of cash flow hedging: Gain (loss) on cash flow hedging relationships: Interest contracts: Amount reclassified from AOCI into income 4,662 11,187 9,318 11,885

Benefit Plans (Tables)

Benefit Plans (Tables)	6 Months Ended
	Jun. 30, 2024
Retirement Benefits [Abstract]
Components of Net Periodic Expense (Benefit)	Defined Benefit Pension Plans Three months ended Six months ended 2024 2023 2024 2023 Interest cost $ 808 $ 871 $ 1,616 $ 1,742 Expected return on plan assets (827) (837) (1,654) (1,674) Settlement (gain) loss (6) 29 (6) 29 Net periodic (benefit) expense $ (25) $ 63 $ (44) $ 97 Other Postretirement Benefit Plan Three months ended Six months ended 2024 2023 2024 2023 Interest cost $ 6 $ 6 $ 12 $ 12 Amortization of prior service credit (7) (31) (15) (62) Amortization of net gain — — (1) (1) Net periodic benefit $ (1) $ (25) $ (4) $ (51)

Reportable Segments (Tables)

Reportable Segments (Tables)	6 Months Ended
	Jun. 30, 2024
Segment Reporting [Abstract]
Summary Financial Information by Reportable Segment	Summarized financial information for the Company’s reportable segments is shown in the following table: Three months ended Six months ended 2024 2023 2024 2023 Sales: Ecoservices $ 153,958 $ 158,065 $ 295,560 $ 295,805 Advanced Materials & Catalysts (1) 28,862 26,045 47,797 49,179 Total $ 182,820 $ 184,110 $ 343,357 $ 344,984 Adjusted EBITDA: (2) Ecoservices $ 49,709 $ 60,136 $ 91,203 $ 96,924 Advanced Materials & Catalysts (3) 14,717 25,371 25,846 38,359 Adjusted EBITDA from reportable segments $ 64,426 $ 85,507 $ 117,049 $ 135,283 (1) Excludes the Company’s proportionate share of sales from the Zeolyst Joint Venture accounted for using the equity method (see Note 9 to these condensed consolidated financial statements for further information). The proportionate share of sales excluded is $29,024 and $52,505 for the three and six months ended June 30, 2024, respectively. The proportionate share of sales excluded is $44,689 and $66,763 for the three and six months ended June 30, 2023, respectively. (2) The Company defines Adjusted EBITDA as EBITDA adjusted for certain items as noted in the reconciliation below. Management evaluates the performance of its segments and allocates resources based on several factors, of which the primary measure is Adjusted EBITDA. Adjusted EBITDA should not be considered as an alternative to net income as an indicator of the Company’s operating performance. Adjusted EBITDA as defined by the Company may not be comparable with EBITDA or Adjusted EBITDA as defined by other companies. (3) The Adjusted EBITDA for the Company’s Advanced Materials & Catalysts segment includes the Company’s 50% portion of the Adjusted EBITDA from the Zeolyst Joint Venture. For the three months ended June 30, 2024, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $5,559, which includes $1,392 of equity in net income plus $940 of amortization of investment in affiliate step-up and $3,227 of joint venture depreciation, amortization and interest. For the six months ended June 30, 2024, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $12,486, which includes $3,464 of equity in net income plus $2,541 of amortization of investment in affiliate step-up and $6,481 of joint venture depreciation, amortization and interest. For the three months ended June 30, 2023, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $16,194, which includes $11,382 of equity in net income plus $1,601 of amortization of investment in affiliate step-up and $3,212 of joint venture depreciation, amortization and interest. For the six months ended June 30, 2023, the Adjusted EBITDA from the Zeolyst Joint Venture included in the Advanced Materials & Catalysts segment was $21,630, which includes $11,608 of equity in net income plus $3,201 of amortization of investment in affiliate step-up and $6,821 of joint venture depreciation, amortization and interest.
Reconciliation of Net Income to Segment Adjusted EBITDA	A reconciliation of income before income taxes to Adjusted EBITDA is as follows: Three months ended Six months ended 2024 2023 2024 2023 Reconciliation of income before income taxes to Adjusted EBITDA from reportable segments Income before income taxes $ 11,375 $ 34,909 $ 13,775 $ 34,385 Interest expense, net 12,895 9,168 26,304 19,000 Depreciation and amortization 21,624 20,969 43,557 41,166 Unallocated corporate expenses 7,532 6,153 14,613 13,080 Joint venture depreciation, amortization and interest 3,227 3,212 6,481 6,821 Amortization of investment in affiliate step-up 940 1,601 2,541 3,201 Debt extinguishment costs 4,560 — 4,560 — Net (gain) loss on asset disposals (34) 1,128 614 2,306 Foreign exchange (gain) loss (99) (398) 79 (1,136) LIFO (benefit) expense (1,547) 1,111 (2,671) 2,510 Transaction and other related costs 140 1,190 198 2,624 Equity-based compensation 3,827 5,002 7,507 9,070 Restructuring, integration and business optimization expenses 159 1,106 385 2,129 Other (173) 356 (894) 127 Adjusted EBITDA from reportable segments $ 64,426 $ 85,507 $ 117,049 $ 135,283

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Valuation Assumptions	The Company used a Monte Carlo simulation to estimate the $11.64 weighted average fair value of the awards granted subject to the TSR goal during the six months ended June 30, 2024, with the following weighted average assumptions: Expected dividend yield — % Risk-free interest rate 4.09 % Expected volatility 39.45 % Expected term (in years) 2.95
Activity of Restricted Stock Units	The following table summarizes the activity for the Company’s RSUs and PSUs for the six months ended June 30, 2024: Restricted Stock Units Performance Stock Units Number of Weighted average grant date fair value (per share) Number of Weighted average grant date fair value (per share) Nonvested as of December 31, 2023 1,962,828 $ 10.55 959,217 (1) $ 11.84 Granted 1,126,166 $ 8.84 535,629 $ 10.23 Vested (999,788) $ 11.10 — $ — Forfeited (21,597) $ 10.19 (126,497) $ 12.99 Nonvested as of June 30, 2024 2,067,609 $ 9.36 1,368,349 (1) $ 11.10 (1) Based on target.
Activity of Performance Stock Units	The following table summarizes the activity for the Company’s RSUs and PSUs for the six months ended June 30, 2024: Restricted Stock Units Performance Stock Units Number of Weighted average grant date fair value (per share) Number of Weighted average grant date fair value (per share) Nonvested as of December 31, 2023 1,962,828 $ 10.55 959,217 (1) $ 11.84 Granted 1,126,166 $ 8.84 535,629 $ 10.23 Vested (999,788) $ 11.10 — $ — Forfeited (21,597) $ 10.19 (126,497) $ 12.99 Nonvested as of June 30, 2024 2,067,609 $ 9.36 1,368,349 (1) $ 11.10 (1) Based on target.

Earnings per Share (Tables)

Earnings per Share (Tables)	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Reconciliation from Basic to Diluted Weighted Average Shares Outstanding	The reconciliation from basic to diluted weighted average shares outstanding is as follows: Three months ended Six months ended 2024 2023 2024 2023 Weighted average shares outstanding – Basic 116,912,332 118,651,402 116,935,708 120,335,414 Dilutive effect of unvested common shares and RSUs with service conditions, PSUs considered probable of vesting and assumed stock option exercises and conversions 722,957 1,269,340 609,532 1,496,528 Weighted average shares outstanding – Diluted 117,635,289 119,920,742 117,545,240 121,831,942
Calculation of Basic and Diluted Earnings per Share	Basic and diluted income per share are calculated as follows: Three months ended Six months ended 2024 2023 2024 2023 Numerator: Net income $ 8,295 $ 26,122 $ 9,516 $ 24,651 Denominator: Weighted average shares outstanding – Basic 116,912,332 118,651,402 116,935,708 120,335,414 Weighted average shares outstanding – Diluted 117,635,289 119,920,742 117,545,240 121,831,942 Net income per share: Basic income per share $ 0.07 $ 0.22 $ 0.08 $ 0.20 Diluted income per share $ 0.07 $ 0.22 $ 0.08 $ 0.20
Anti-dilutive Shares	The table below presents the details of the Company’s weighted average equity-based awards outstanding during each respective period that were excluded from the calculation of diluted earnings per share: Three months ended Six months ended 2024 2023 2024 2023 RSAs with performance only targets not achieved — — — 99,495 Stock options with performance only targets not achieved — — — 103,907 Anti-dilutive RSUs and PSUs 431,837 685,656 481,281 630,668 Anti-dilutive stock options 367,100 520,757 367,100 607,783

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information (Tables)	6 Months Ended
	Jun. 30, 2024
Supplemental Cash Flow Elements [Abstract]
Schedule of Cash Flow, Supplemental Disclosures	The following table presents supplemental cash flow information for the Company: Six months ended 2024 2023 Cash paid during the period for: Income taxes, net of refunds $ 16,439 $ 9,955 Interest (1) 33,155 19,391 Non-cash investing activity: Capital expenditures acquired on account but unpaid as of the period end 784 605 Non-cash financing activity: Accrued excise tax on share repurchases (Note 5) — 630 Right-of-use assets obtained in exchange for new lease liabilities (non-cash): Operating leases 2,957 6,202 (1) Cash paid for interest is shown net of capitalized interest and includes the cash received or paid on the Company’s interest rate cap agreements designated as cash flow hedges for the periods presented (see Note 12 to these condensed consolidated financial statements for details).

Background and Basis of Prese_3

Background and Basis of Presentation (Details)	6 Months Ended
	Jun. 30, 2024 reporting_unit
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reporting units	2

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	$ 182,820	$ 184,110	$ 343,357	$ 344,984
Clean fuels, emission control & other
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	8,614	8,426	16,003	13,166
Polyethylene, polymers & engineered plastics
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	28,862	26,045	47,797	49,179
Regeneration and treatment services
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	95,365	98,494	178,684	186,838
Industrial, mining & automotive
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	49,979	51,145	100,873	95,801
Ecoservices
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	153,958	158,065	295,560	295,805
Ecoservices | Clean fuels, emission control & other
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	8,614	8,426	16,003	13,166
Ecoservices | Polyethylene, polymers & engineered plastics
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Ecoservices | Regeneration and treatment services
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	95,365	98,494	178,684	186,838
Ecoservices | Industrial, mining & automotive
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	49,979	51,145	100,873	95,801
Advanced Materials & Catalysts
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	28,862	26,045	47,797	49,179
Advanced Materials & Catalysts | Clean fuels, emission control & other
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Advanced Materials & Catalysts | Polyethylene, polymers & engineered plastics
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	28,862	26,045	47,797	49,179
Advanced Materials & Catalysts | Regeneration and treatment services
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Advanced Materials & Catalysts | Industrial, mining & automotive
Disaggregated Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	$ 0	$ 0	$ 0	$ 0

Fair Value Measurements (Detail

Fair Value Measurements (Details) - Recurring - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Derivative assets:
Interest rate caps	$ 19,965	$ 19,021
Derivative liabilities:
Derivative Liability	403	2,496
Quoted Prices in Active Markets (Level 1)
Derivative assets:
Interest rate caps	0	0
Derivative liabilities:
Derivative Liability	0	0
Significant Other Observable Inputs (Level 2)
Derivative assets:
Interest rate caps	19,965	19,021
Derivative liabilities:
Derivative Liability	403	2,496
Significant Unobservable Inputs (Level 3)
Derivative assets:
Interest rate caps	0	0
Derivative liabilities:
Derivative Liability	$ 0	$ 0

Stockholders' Equity - Pre-tax

Stockholders' Equity - Pre-tax and After-tax Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Other Comprehensive Income (Loss) [Line Items]
Pre-tax amount	$ (1,405)		$ 8,507		$ 2,054	$ 357
Tax benefit/ (expense)	181		(1,815)		(1,104)	576
Total other comprehensive (loss) income	(1,224)	$ 2,174	6,692	$ (5,759)	950	933
Defined benefit and other postretirement plans
Other Comprehensive Income (Loss) [Line Items]
Pre-tax amount	707		620		698	588
Tax benefit/ (expense)	(177)		(155)		(174)	(147)
Total other comprehensive (loss) income	530		465		524	441
Net gain
Other Comprehensive Income (Loss) [Line Items]
Pre-tax amount	714		651		713	650
Tax benefit/ (expense)	(178)		(162)		(178)	(162)
Total other comprehensive (loss) income	536		489		535	488
Net prior service cost
Other Comprehensive Income (Loss) [Line Items]
Pre-tax amount	(7)		(31)		(15)	(62)
Tax benefit/ (expense)	1		7		4	15
Total other comprehensive (loss) income	(6)		(24)		(11)	(47)
Net (loss) gain from hedging activities
Other Comprehensive Income (Loss) [Line Items]
Pre-tax amount	(1,433)		7,059		3,719	(3,244)
Tax benefit/ (expense)	358		(1,660)		(930)	723
Total other comprehensive (loss) income	(1,075)		5,399		2,789	(2,521)
Foreign currency translation
Other Comprehensive Income (Loss) [Line Items]
Pre-tax amount	(679)		828		(2,363)	3,013
Tax benefit/ (expense)	0		0		0	0
Total other comprehensive (loss) income	$ (679)		$ 828		$ (2,363)	$ 3,013

Stockholders' Equity - Change b

Stockholders' Equity - Change by Component (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 711,356	$ 705,464	$ 674,151	$ 707,229	$ 705,464	$ 707,229
Other comprehensive income (loss) before reclassifications					7,955	9,817
Amounts reclassified from accumulated other comprehensive income					(7,005)	(8,884)
Total other comprehensive (loss) income	(1,224)	2,174	6,692	(5,759)	950	933
Ending balance	717,283	711,356	667,764	674,151	717,283	667,764
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	1,216	(958)	233	5,992	(958)	5,992
Total other comprehensive (loss) income	(1,224)	2,174	6,692	(5,759)
Ending balance	(8)	1,216	6,925	233	(8)	6,925
Defined benefit and other postretirement plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		612		(508)	612	(508)
Other comprehensive income (loss) before reclassifications					540	412
Amounts reclassified from accumulated other comprehensive income					(16)	29
Total other comprehensive (loss) income	530		465		524	441
Ending balance	1,136		(67)		1,136	(67)
Gain (loss) on cash flow hedging relationships:
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		12,546		24,672	12,546	24,672
Other comprehensive income (loss) before reclassifications					9,778	6,392
Amounts reclassified from accumulated other comprehensive income					(6,989)	(8,913)
Total other comprehensive (loss) income	(1,075)		5,399		2,789	(2,521)
Ending balance	15,335		22,151		15,335	22,151
Foreign currency translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		$ (14,116)		$ (18,172)	(14,116)	(18,172)
Other comprehensive income (loss) before reclassifications					(2,363)	3,013
Amounts reclassified from accumulated other comprehensive income					0	0
Total other comprehensive (loss) income	(679)		828		(2,363)	3,013
Ending balance	$ (16,479)		$ (15,159)		$ (16,479)	$ (15,159)

Stockholders' Equity - Reclassi

Stockholders' Equity - Reclassifications out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (expense) income	$ (410)		$ (610)		$ (627)	$ (182)
Total before tax	11,375		34,909		13,775	34,385
Interest expense, net	(12,895)		(9,168)		(26,304)	(19,000)
Tax expense	(3,080)		(8,787)		(4,259)	(9,734)
Net income	8,295	$ 1,221	26,122	$ (1,471)	9,516	24,651
Amounts Reclassified from Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	3,506		8,385		7,005	8,884
Defined benefit and other postretirement plans  | Amounts Reclassified from Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	13		(2)		22	(34)
Tax expense	(3)		0		(6)	5
Net income	10		(2)		16	(29)
Net gain | Amounts Reclassified from Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (expense) income	6		29		7	28
Net prior service cost | Amounts Reclassified from Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other (expense) income	7		(31)		15	(62)
Gain (loss) on cash flow hedging relationships: | Amounts Reclassified from Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense, net	4,662		11,187		9,318	11,885
Tax expense	(1,166)		(2,800)		(2,329)	(2,972)
Net income	$ 3,496		$ 8,387		$ 6,989	$ 8,913

Stockholders' Equity - Narrativ

Stockholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended				6 Months Ended
	Apr. 27, 2022	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Equity, Class of Treasury Stock [Line Items]
Repurchases of common shares		$ 5,010		$ 43,524	$ 29,850
Shares withheld for tax withholding obligation (in shares)						128,801	95,269
Fair value of shares withheld for tax payments			$ 1,218		$ 866	$ 1,218	$ 866
Stock Repurchase Program 2022
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount	$ 450,000
Stock repurchase program, period (in years)	4 years
Shares acquired (in shares)						552,081	7,000,000
Average cost per share (in dollars per share)						$ 9.05	$ 10.48
Repurchases of common shares						$ 4,998	$ 73,373
Remaining authorized repurchase amount		$ 229,594				229,594
Excise tax						$ 0	$ 630

Goodwill - Schedule of Goodwill

Goodwill - Schedule of Goodwill (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2024 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 404,470
Foreign exchange impact	(195)
Ending balance	404,275
Ecoservices
Goodwill [Roll Forward]
Beginning balance	326,589
Foreign exchange impact	0
Ending balance	326,589
Advanced Materials & Catalysts
Goodwill [Roll Forward]
Beginning balance	77,881
Foreign exchange impact	(195)
Ending balance	$ 77,686

Goodwill - Narrative (Details)

Goodwill - Narrative (Details)	Oct. 01, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Percentage of fair value in excess of carrying amount	30%

Other Operating Expense, Net (D

Other Operating Expense, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Other Income and Expenses [Abstract]
Amortization expense	$ 2,644	$ 2,643	$ 5,289	$ 5,280
Transaction and other related costs	140	1,190	198	2,624
Restructuring, integration and business optimization costs	159	1,106	385	2,129
Net (gain) loss on asset disposals	(34)	1,128	614	2,306
Other, net	199	195	288	641
Total other operating expense, net	$ 3,108	$ 6,262	$ 6,774	$ 12,980

Inventories, Net (Details)

Inventories, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Inventory Disclosure [Abstract]
Finished products and work in process	$ 48,536	$ 41,658
Raw materials	3,491	3,457
Inventories, net	52,027	45,115
Valued at lower of cost or market:
LIFO basis	30,003	24,815
Valued at lower of cost and net realizable value:
FIFO or average cost basis	$ 22,024	$ 20,300

Investments in Affiliated Com_3

Investments in Affiliated Companies - Ownership Percentage (Details)	Jun. 30, 2024
Zeolyst International
Schedule of Equity Method Investments [Line Items]
Percent ownership	50%
Zeolyst C.V.
Schedule of Equity Method Investments [Line Items]
Percent ownership	50%

Investments in Affiliated Com_4

Investments in Affiliated Companies - Summarized Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Schedule of Equity Method Investments [Line Items]
Gross profit	$ 53,663		$ 60,970		$ 92,886	$ 97,464
Operating income	27,848		33,313		41,802	41,970
Net income	8,295	$ 1,221	26,122	$ (1,471)	9,516	24,651
Equity Method Investment, Nonconsolidated Investee
Schedule of Equity Method Investments [Line Items]
Sales	70,644		99,188		127,505	155,085
Gross profit	16,751		34,461		33,929	44,571
Operating income	5,739		25,103		12,583	27,502
Net income	$ 4,665		$ 25,926		$ 12,010	$ 29,573

Investments in Affiliated Com_5

Investments in Affiliated Companies - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Business Combination
Amortization of investment in affiliate step-up	$ (940)	$ (1,601)	$ (2,541)	$ (3,201)
Accounts payable	34,195		34,195		$ 40,195
Related Party
Business Combination
Accounts receivable, after allowance for credit loss	5,018		5,018		3,231
Accounts payable	2,859		2,859		1,351
Sales	2,110	757	2,110	2,457
Purchases from related party	0	0	0	0
Business Combination
Business Combination
Net purchase accounting fair value adjustments	222,073		222,073		$ 224,614
Amortization of investment in affiliate step-up	$ 940	$ 1,601	$ 2,541	$ 3,201

Property, Plant and Equipment -

Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment
Property, plant and equipment, gross	$ 1,076,218	$ 1,044,202
Less: accumulated depreciation	(502,659)	(467,298)
Property, plant and equipment, net	573,559	576,904
Land
Property, Plant and Equipment
Property, plant and equipment, gross	96,807	96,833
Buildings and improvements
Property, Plant and Equipment
Property, plant and equipment, gross	92,085	84,860
Machinery and equipment
Property, Plant and Equipment
Property, plant and equipment, gross	851,706	820,509
Construction in progress
Property, Plant and Equipment
Property, plant and equipment, gross	$ 35,620	$ 42,000

Property, Plant and Equipment_2

Property, Plant and Equipment - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Property, Plant and Equipment [Abstract]
Depreciation	$ 18,108	$ 17,455	$ 36,523	$ 34,147

Long-term Debt - Summary of Lon

Long-term Debt - Summary of Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Instrument
Total debt	$ 873,000	$ 877,500
Original issue discount	(7,621)	(6,162)
Deferred financing costs	(2,974)	(3,392)
Total debt, net of original issue discount and deferred financing costs	862,405	867,946
Less: current portion	(6,548)	(9,000)
Total long-term debt, excluding current portion	855,857	858,946
2024 Term Loan Facility
Debt Instrument
Total debt	873,000	877,500
ABL Facility
Debt Instrument
Total debt	$ 0	$ 0

Long-term Debt - Narrative (Det

Long-term Debt - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2024	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Debt Instrument
Debt extinguishment costs			$ 90	$ 0
2021 Term Loan Facility
Debt Instrument
Unamortized deferred financing costs		$ 30	30
Unamortized discount, write off		59	59
2021 Term Loan Facility | Secured Overnight Financing Rate (SOFR) | Variable Rate Component One
Debt Instrument
Variable rate on spread	2.25%
2021 Term Loan Facility | Secured Overnight Financing Rate (SOFR) | Minimum | Variable Rate Component Two
Debt Instrument
Variable rate on spread	1.25%
2021 Term Loan Facility | Secured Overnight Financing Rate (SOFR) | Maximum | Variable Rate Component One
Debt Instrument
Variable rate on spread	2.75%
2021 Term Loan Facility | Secured Overnight Financing Rate (SOFR) | Maximum | Variable Rate Component Two
Debt Instrument
Variable rate on spread	1.75%
2024 Term Loan Facility
Debt Instrument
Debt extinguishment costs		4,471	4,471
Unamortized discount, noncurrent	$ 2,183	2,183	2,183
Long-term debt, fair value	$ 873,000	$ 873,000	$ 873,000		$ 876,403
2024 Term Loan Facility | Secured Overnight Financing Rate (SOFR)
Debt Instrument
Credit spread adjustment	0.10%
Effective interest rate	7.59%	7.59%	7.59%
ABL Facility | Secured Overnight Financing Rate (SOFR)
Debt Instrument
Credit spread adjustment			0.10%
Effective interest rate	8.75%	8.75%	8.75%
ABL Facility | Secured Overnight Financing Rate (SOFR) | Minimum
Debt Instrument
Variable rate on spread			1.25%
ABL Facility | Secured Overnight Financing Rate (SOFR) | Maximum
Debt Instrument
Variable rate on spread			1.75%
ABL Facility | Base Rate | Minimum
Debt Instrument
Variable rate on spread			0.25%
ABL Facility | Base Rate | Maximum
Debt Instrument
Variable rate on spread			0.75%

Financial Instruments - Interes

Financial Instruments - Interest Rate Cap Agreements (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2024 USD ($) derivative derivative_instrument_held
Derivative
Number of instruments | derivative	4
Annuitized premium of instruments in effect	$ 24,817
Cash flow hedging
Derivative
Number of instruments in effect | derivative_instrument_held	3
Current notional amount of instruments in effect	$ 650,000

Financial Instruments - Narrati

Financial Instruments - Narrative (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2024 USD ($) derivative_instrument_held
Derivative
Amount of derivative loss expected to be transferred from OCI	$ 8,700
Cash flow hedging
Derivative
Number of instruments in effect | derivative_instrument_held	3
Notional amount	$ 650,000
Derivative, cap interest rate	1%
Cash flow hedging | Interest Rate Cap One
Derivative
Notional amount	$ 250,000
Cash flow hedging | Interest Rate Cap Two
Derivative
Notional amount	250,000
Cash flow hedging | Interest Rate Cap Three
Derivative
Notional amount	150,000
Cash flow hedging | Interest Rate Cap Three Period Two
Derivative
Notional amount	$ 175,000

Financial Instruments - Fair Va

Financial Instruments - Fair Values of Derivative Instruments Held (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Derivative assets
Derivative asset, current	$ 12,270	$ 13,419
Derivative Asset, Current, Statement of Financial Position [Extensible Enumeration]	Prepaid and other current assets	Prepaid and other current assets
Derivative Asset, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other long-term assets	Other long-term assets
Derivative liabilities
Derivative Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other long-term liabilities	Other long-term liabilities
Derivatives designated as hedging instrument | Cash flow hedging | Interest rate caps
Derivative assets
Derivative asset, current	$ 12,270	$ 13,419
Derivative asset, noncurrent	7,695	5,602
Interest rate caps	19,965	19,021
Derivative liabilities
Derivative liability, noncurrent	403	2,496
Derivative liability	$ 403	$ 2,496

Financial Instruments - Effect

Financial Instruments - Effect of Derivative Instruments Designated as Hedges on Other Comprehensive Income (Details) - Interest rate caps - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Amount of gain (loss) reclassified from AOCI into income
Amount of gain (loss) recognized in OCI on derivatives	$ 3,229	$ 18,246	$ 13,037	$ 8,641
Interest (expense) income
Amount of gain (loss) reclassified from AOCI into income
Amount of gain (loss) reclassified from AOCI into income	$ (4,662)	$ 11,187	$ (9,318)	$ 11,885

Financial Instruments - Cash Fl

Financial Instruments - Cash Flow Hedge Impact on Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Derivative
Interest expense, net	$ (12,895)	$ (9,168)	$ (26,304)	$ (19,000)
Amount reclassified from AOCI into income | Gain (loss) on cash flow hedging relationships:
Derivative
Interest expense, net	$ 4,662	$ 11,187	$ 9,318	$ 11,885

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Effective income tax rate	27.10%	25.20%	30.90%	28.30%

Benefit Plans (Details)

Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Defined Benefit Pension Plans
Defined Benefit Plan, Net Periodic Expense (Benefit)
Interest cost	$ 808	$ 871	$ 1,616	$ 1,742
Expected return on plan assets	(827)	(837)	(1,654)	(1,674)
Settlement (gain) loss	(6)	29	(6)	29
Net periodic (benefit) expense	(25)	63	(44)	97
Other Postretirement Benefits Plan
Defined Benefit Plan, Net Periodic Expense (Benefit)
Interest cost	6	6	12	12
Amortization of prior service credit	(7)	(31)	(15)	(62)
Amortization of net gain	0	0	(1)	(1)
Net periodic (benefit) expense	$ (1)	$ (25)	$ (4)	$ (51)

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Related Party Transaction [Line Items]
Accounts payable, related parties	$ 34,195		$ 34,195		$ 40,195
Related Party
Related Party Transaction [Line Items]
Sales	2,110	$ 757	2,110	$ 2,457
Purchases from related party	0	0	0	0
Accounts receivable, after allowance for credit loss	5,018		5,018		3,231
Accounts payable, related parties	2,859		2,859		1,351
Related Party | Corporate Joint Venture
Related Party Transaction [Line Items]
Accounts receivable, after allowance for credit loss	5,008		5,008		3,164
Accounts payable, related parties	0		0		$ 0
Related Party | Operating Lease Rental Payments | Corporate Joint Venture
Related Party Transaction [Line Items]
Sales	78	155	78	155
Related Party | Sales from Partnership to Company
Related Party Transaction [Line Items]
Purchases from related party	0	0	0	0
Related Party | Manufacturing Costs | Corporate Joint Venture
Related Party Transaction [Line Items]
Sales	6,050	5,028	10,084	10,869
Related Party | Services | Corporate Joint Venture
Related Party Transaction [Line Items]
Sales	4,600	3,618	8,900	7,252
Related Party | Product Demonstration Costs | Corporate Joint Venture
Related Party Transaction [Line Items]
Sales	$ 238	$ 428	$ 595	$ 928

Reportable Segments - Summary F

Reportable Segments - Summary Financial Information by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting
Sales	$ 182,820	$ 184,110	$ 343,357	$ 344,984
Adjusted EBITDA from reportable segments	64,426	85,507	117,049	135,283
Equity in net income from affiliated companies	1,392	11,374	3,464	11,597
Amortization of investment in affiliate step-up	940	1,601	2,541	3,201
Joint venture depreciation, amortization and interest	3,227	3,212	6,481	6,821
Ecoservices
Segment Reporting
Sales	153,958	158,065	295,560	295,805
Adjusted EBITDA from reportable segments	49,709	60,136	91,203	96,924
Advanced Materials & Catalysts
Segment Reporting
Sales	28,862	26,045	47,797	49,179
Adjusted EBITDA from reportable segments	14,717	25,371	25,846	38,359
Advanced Materials & Catalysts | Zeolyst Joint Venture
Segment Reporting
Sales	29,024	44,689	52,505	66,763
Adjusted EBITDA from reportable segments	$ 5,559	16,194	$ 12,486	21,630
Percent ownership	50%		50%
Equity in net income from affiliated companies	$ 1,392	11,382	$ 3,464	11,608
Amortization of investment in affiliate step-up	940	1,601	2,541	3,201
Joint venture depreciation, amortization and interest	$ 3,227	$ 3,212	$ 6,481	$ 6,821

Reportable Segments - Reconcili

Reportable Segments - Reconciliation of Net Income to Segment Adjusted EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting [Abstract]
Income before income taxes	$ 11,375	$ 34,909	$ 13,775	$ 34,385
Interest expense, net	12,895	9,168	26,304	19,000
Depreciation and amortization	21,624	20,969	43,557	41,166
Unallocated corporate expenses	7,532	6,153	14,613	13,080
Joint venture depreciation, amortization and interest	3,227	3,212	6,481	6,821
Amortization of investment in affiliate step-up	940	1,601	2,541	3,201
Debt extinguishment costs	4,560	0	4,560	0
Net (gain) loss on asset disposals	(34)	1,128	614	2,306
Foreign exchange (gain) loss	(99)	(398)	79	(1,136)
LIFO (benefit) expense	(1,547)	1,111	(2,671)	2,510
Transaction and other related costs	140	1,190	198	2,624
Equity-based compensation	3,827	5,002	7,507	9,070
Restructuring, integration and business optimization expenses	159	1,106	385	2,129
Other	(173)	356	(894)	127
Adjusted EBITDA from reportable segments	$ 64,426	$ 85,507	$ 117,049	$ 135,283

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details)	Jun. 30, 2024 shares
Share-Based Payment Arrangement [Abstract]
Number of shares available for grant (in shares)	8,032,299

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units and Performance Stock Units (Details)	1 Months Ended	6 Months Ended
	Feb. 29, 2024	Jun. 30, 2024 $ / shares shares
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Granted (in shares) | shares		1,126,166
Granted, weighted average grant date fair value (in dollars per share) | $ / shares		$ 8.84
Restricted Stock Units | Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award
Award requisite service period (in years)		1 year
Restricted Stock Units | Employee
Share-based Compensation Arrangement by Share-based Payment Award
Award requisite service period (in years)		3 years
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Granted (in shares) | shares		535,629
Granted, weighted average grant date fair value (in dollars per share) | $ / shares		$ 10.23
Performance Stock Units | 2024 Grants
Share-based Compensation Arrangement by Share-based Payment Award
Granted (in shares) | shares		535,629
Award requisite performance period		3 years
Granted, weighted average grant date fair value (in dollars per share) | $ / shares		$ 11.64
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected dividend yield		0%
Risk-free interest rate		4.09%
Expected volatility		39.45%
Expected term (in years)		2 years 11 months 12 days
Performance Stock Units | 2024 Grants | Company Performance Measure
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Granted, percentage of target		0.50
Performance Stock Units | 2024 Grants | Total Shareholder Return (TSR)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Granted, percentage of target		0.50
Performance Stock Units | 2024 Grants | Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting percentage		50%
Performance Stock Units | 2024 Grants | Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting percentage		200%
Performance Stock Units | 2021 Grants
Share-based Compensation Arrangement by Share-based Payment Award
Award requisite service period (in years)	3 years

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of RSU and PSU Activity (Details)	6 Months Ended
	Jun. 30, 2024 $ / shares shares
Restricted Stock Units
Number of units
Nonvested, beginning balance (in shares) | shares	1,962,828
Granted (in shares) | shares	1,126,166
Vested (in shares) | shares	(999,788)
Forfeited (in shares) | shares	(21,597)
Nonvested, ending balance (in shares) | shares	2,067,609
Weighted average grant date fair value (per share)
Nonvested, beginning balance (in dollars per share) | $ / shares	$ 10.55
Granted (in dollars per share) | $ / shares	8.84
Vested (in dollars per share) | $ / shares	11.10
Forfeited (in dollars per share) | $ / shares	10.19
Nonvested, ending balance (in dollars per share) | $ / shares	$ 9.36
Performance Stock Units
Number of units
Nonvested, beginning balance (in shares) | shares	959,217
Granted (in shares) | shares	535,629
Vested (in shares) | shares	0
Forfeited (in shares) | shares	(126,497)
Nonvested, ending balance (in shares) | shares	1,368,349
Weighted average grant date fair value (per share)
Nonvested, beginning balance (in dollars per share) | $ / shares	$ 11.84
Granted (in dollars per share) | $ / shares	10.23
Vested (in dollars per share) | $ / shares	0
Forfeited (in dollars per share) | $ / shares	12.99
Nonvested, ending balance (in dollars per share) | $ / shares	$ 11.10
RSAs with performance only targets not achieved
Number of units
Granted (in shares) | shares	4,540
Weighted average grant date fair value (per share)
Granted (in dollars per share) | $ / shares	$ 8.81

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award
Stock compensation expense	$ 3,827	$ 5,002	$ 7,507	$ 9,070
Stock-based compensation expense, tax benefit	939	$ 1,181	$ 1,841	$ 2,154
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Forfeited, performance-based restricted shares (in shares)			21,597
Unrecognized stock-based compensation expense	14,391		$ 14,391
Unrecognized stock-based compensation expense, period for recognition			1 year 10 months 2 days
Performance Stock Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Unrecognized stock-based compensation expense	$ 9,474		$ 9,474
Unrecognized stock-based compensation expense, period for recognition			2 years 1 month 17 days

Earnings per Share - Reconcilia

Earnings per Share - Reconciliation from Basic to Diluted Weighted Average Shares Outstanding (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Earnings Per Share [Abstract]
Weighted average shares outstanding – Basic (in shares)	116,912,332	118,651,402	116,935,708	120,335,414
Dilutive effect of unvested common shares and restricted stock units with service conditions, performance stock units considered probable of vesting and assumed stock option exercises and conversions (in shares)	722,957	1,269,340	609,532	1,496,528
Weighted average shares outstanding – Diluted (in shares)	117,635,289	119,920,742	117,545,240	121,831,942

Earnings per Share - Calculatio

Earnings per Share - Calculation of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Numerator:
Net income	$ 8,295	$ 1,221	$ 26,122	$ (1,471)	$ 9,516	$ 24,651
Denominator:
Weighted average shares outstanding – Basic (in shares)	116,912,332		118,651,402		116,935,708	120,335,414
Weighted average shares outstanding – Diluted (in shares)	117,635,289		119,920,742		117,545,240	121,831,942
Net income per share:
Basic income per share (in dollars per share)	$ 0.07		$ 0.22		$ 0.08	$ 0.20
Diluted income per share (in dollars per share)	$ 0.07		$ 0.22		$ 0.08	$ 0.20

Earnings per Share - Anti-dilut

Earnings per Share - Anti-dilutive Shares (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
RSAs with performance only targets not achieved
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive stock options (in shares)	0	0	0	99,495
Stock options with performance only targets not achieved
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive stock options (in shares)	0	0	0	103,907
Anti-dilutive RSUs and PSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive stock options (in shares)	431,837	685,656	481,281	630,668
Anti-dilutive stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive stock options (in shares)	367,100	520,757	367,100	607,783

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash paid during the period for:
Income taxes, net of refunds	$ 16,439	$ 9,955
Interest	33,155	19,391
Non-cash investing activity:
Capital expenditures acquired on account but unpaid as of the period end	784	605
Non-cash financing activity:
Accrued excise tax on share repurchases (Note 5)	0	630
Right-of-use assets obtained in exchange for new lease liabilities (non-cash):
Operating leases	$ 2,957	$ 6,202

Subsequent Events (Details)

Subsequent Events (Details) $ in Thousands	Jul. 24, 2024 USD ($)
Subsequent Event
Subsequent Event [Line Items]
Equity method investment, aggregate cost	$ 4,500