COMMITMENTS AND CONTINGENCIES	6 Months Ended
COMMITMENTS AND CONTINGENCIES	Jun. 30, 2026
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	Note 10 — COMMITMENTS AND CONTINGENCIES We have been notified by federal and state environmental agencies and by private parties that we may be a potentially responsible party (PRP) in connection with the environmental investigation and remediation of certain sites. While government agencies frequently assert that PRPs are jointly and severally liable at these sites, in our experience, the interim and final allocations of liability costs are generally made based on the relative contribution of waste. We may also initiate corrective and preventive environmental projects of our own to support safe and lawful activities at our operations. In September 2007, the United States District Court for the Western District of Kentucky (Court) in the case of Westlake Vinyls, Inc. v. Goodrich Corporation, et al., held that Avient must pay the remediation costs at the former Goodrich Corporation Calvert City facility (now largely owned and operated by Westlake Vinyls, Inc. (Westlake Vinyls)), together with certain defense costs of Goodrich Corporation. The rulings also provided that Avient can seek indemnification for contamination attributable to Westlake Vinyls. Following the rulings, the parties to the litigation agreed to settle all claims regarding past environmental costs incurred at the site. The settlement agreement provides a mechanism to pursue allocation of future remediation costs at the Calvert City site to Westlake Vinyls. The environmental obligation at the site arose as a result of an agreement between The B.F. Goodrich Company (n/k/a Goodrich Corporation) and our predecessor, The Geon Company (Geon), at the time of Geon’s initial public offering in 1993. Under the agreement, Geon agreed to indemnify Goodrich Corporation for certain environmental costs at the site. Neither Avient nor Geon ever operated the facility. Since 2009, Avient, along with respondents Westlake Vinyls and Goodrich Corporation, has worked with the United States Environmental Protection Agency (USEPA) to address the remedial activities at the site. The USEPA issued its Record of Decision (ROD) in September 2018. In April 2019, the respondents signed an Administrative Settlement Agreement and Order on Consent with the USEPA to complete remedial designs for the site. In February 2020, three companies signed the agreed Consent Decree and remedial action Work Plan to conduct the remedial action at the site, which received Federal Court approval in January 2021. In 2024, the Company finalized the design for the first phase of a barrier wall and construction of this phase was completed in 2025. In 2025, the Company recognized charges of $21.3 million associated with incremental investigation and remedial design work deemed necessary based on results of ongoing findings at the site. This incremental work resulted in a two-year extension of the planned remedial action timeline, which also contributed to the charges. The remaining wall designs and construction are expected to be completed in phases and, depending on the outcome of additional investigations and finalization of remedial designs, may extend beyond 2030. As remedial design and supporting analyses have advanced in 2026, Avient has identified the need for certain modifications to the initially contemplated remedy. In addition, the USEPA has issued a modification to the ROD that lowers certain tolerance thresholds of clean up criterion at the site and has also requested evaluations of additional design criteria that may materially affect design requirements and construction costs. As a result, further design efforts are required, including updated analyses of construction approaches and methodologies. Certain design criteria currently under evaluation may ultimately not be incorporated into the final remedy. Given the ongoing analyses and associated design evaluations, the impact of the lowered tolerance threshold of clean up criterion and potential additional modifications under evaluation cannot yet be reasonably estimated. As remedial design progresses, including refinement of the overall implementation schedule and required remedy modifications, Avient will update its environmental reserve as appropriate. The accrual associated with Calvert City was $123.1 million as of June 30, 2026 and $133.2 million as of December 31, 2025. Total environmental accruals of $132.3 million and $141.2 million are reflected within Accrued expenses and other current liabilities and Other non-current liabilities in our Condensed Consolidated Balance Sheets as of June 30, 2026 and December 31, 2025, respectively. These undiscounted accruals represent our best estimate of probable future costs that we can reasonably estimate, based upon currently available information and technology and how the remedy will be implemented. Previous adjustments to the Calvert City environmental accrual have had a material impact on our Condensed Consolidated Statements of Income in the periods recognized. Due to the scale and complexity of the remedial actions required at Calvert City, it is probable that additional costs will be incurred in excess of the amounts accrued, which would have a material impact on our Condensed Consolidated Statements of Income, in the period recognized. However, such additional costs cannot currently be estimated as they are dependent upon the results of future testing and findings during the execution of remedial design and remedial action, changes to the construction timeline, changes in regulations, technology development, new information, newly discovered conditions and other factors that are not currently known. During the three and six months ended June 30, 2026, Avient recognized costs of $4.7 million and $8.6 million, primarily associated with the ongoing remedial design and remedial action at Calvert City, compared to costs of $1.8 million and $6.7 million recognized during the three and six months ended June 30, 2025. These costs are recognized in Cost of Sales within the Condensed Consolidated Statements of Income. We received $34.0 million of cash associated with Calvert City insurance recoveries in the first quarter of 2025. The associated gain was recognized in the fourth quarter of 2024. Further insurance recoveries, if any, related to remedial activities at the Calvert City site are expected to be immaterial. Avient is subject to a broad range of claims, administrative and legal proceedings such as lawsuits that relate to contractual allegations, tax audits, product claims, personal injuries and employment related matters. Although it is not possible to predict with certainty the outcome or cost of these matters, the Company believes our current reserves are appropriate and these matters will not have a material adverse effect on the condensed consolidated financial statements.