BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
	Sep. 30, 2025
Basis Of Presentation [Abstract]
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES In the opinion of management, the accompanying condensed consolidated financial statements of Tredegar Corporation and its subsidiaries (“Tredegar,” “the Company,” “we,” “us” or “our”) contain all adjustments necessary to state fairly, in all material respects, Tredegar’s condensed consolidated financial position as of September 30, 2025, the condensed consolidated results of operations for the three and nine months ended September 30, 2025 and 2024, the condensed consolidated cash flows for the nine months ended September 30, 2025 and 2024, and the condensed consolidated changes in shareholders’ equity for the three and nine months ended September 30, 2025 and 2024, in accordance with U.S. generally accepted accounting principles (“GAAP”). All such adjustments, unless otherwise detailed in the notes to the condensed consolidated financial statements, are deemed to be of a normal, recurring nature. The Company operates on a calendar fiscal year except for the Aluminum Extrusions segment, which operates on a 52/53-week fiscal year basis. As such, the fiscal third quarter for 2025 and 2024 for this segment references 13-week periods ended September 28, 2025 and September 29, 2024, respectively. The Company does not believe the impact of reporting the results of this segment as stated above is material to the consolidated financial results. The Company may fund or receive cash from the Aluminum Extrusions segment based on Aluminum Extrusion’s cash flows from operations during the intervening period from Aluminum Extrusion’s fiscal quarter end and the Company’s fiscal quarter end. As a result, the Company’s cash and cash equivalents declined by $3.6 million as of December 31, 2024 since the Company made payments to the Aluminum Extrusions segment to fund its working capital during the intervening period. There was no intercompany funding with Aluminum Extrusions between September 28, 2025 and September 30, 2025. The condensed consolidated financial statements as of December 31, 2024 that is included herein was derived from the audited consolidated financial statements provided in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 (“2024 Form 10-K”) but does not include all disclosures required by GAAP. These financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in the 2024 Form 10-K. The results of operations for the three and nine months ended September 30, 2025, are not necessarily indicative of the results to be expected for the full year. Sale of Flexible Packaging Films On November 1, 2024, the Company completed the sale of its flexible packaging films business (also referred to as “Terphane”) headquartered in Brazil to Oben Group (“Oben”). Commencing in the fourth quarter of 2024, all historical results for Terphane have been presented as discontinued operations. For more information on this transaction, see Note 11. Closure of PE Films Technical Center In August 2023, the Company adopted a plan to close the PE Films technical center in Richmond, VA and reduce its efforts to develop and sell films supporting the semiconductor market. Research & development activities for PE Films are now being performed at the production facility in Pottsville, PA. PE Films continues to have new business opportunities primarily relating to surface protection films that protect components of flat panel and flexible displays. All activities ceased at the PE Films technical center in Richmond, VA as of the end of the first quarter of 2024. Accounting standards not yet adopted In October 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2023-06 to amend various paragraphs in the Accounting Standards Codification ("ASC") to primarily reflect the issuance of U.S. Securities and Exchange Commission ("SEC") Staff Bulletin No. 33-10532. ASU 2023-06 will impact various disclosure areas, including the statement of cash flows, accounting changes and error corrections, earnings per share, debt, equity, derivatives, and transfers of financial assets. The amendments in this ASU 2023-06 will be effective on the date the related disclosures are removed from Regulation S-X or Regulation S-K by the SEC and will no longer be effective if the SEC has not removed the applicable disclosure requirement by June 30, 2027. Early adoption is not permitted. The Company does not expect a material impact from the adoption of this standard on our consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU 2023-09 to improve the income tax disclosures related to the rate reconciliation and income taxes paid information and to improve the effectiveness of income tax disclosures. The amendments in this ASU will require the Company to disclose specified additional information in its income tax rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold. ASU 2023-09 will also require the Company to disaggregate its income taxes paid disclosure by federal, state and foreign taxes, with further disaggregation required for significant individual jurisdictions. This ASU is effective for annual periods beginning after December 15, 2024; early adoption is permitted. The Company will adopt this ASU on a prospective basis and continues to evaluate additional disclosures that may be required in its Annual Report on Form 10-K for the year ended December 31, 2025. In November 2024, the FASB issued ASU 2024-03 to improve the disclosures about public business entity’s expenses and address requests from investors for more detailed information about the types of expenses in commonly presented expense captions. The amendments in this ASU will require the Company to disclose specified information about certain costs and expenses in the notes to the financial statements. This ASU is effective for annual periods beginning after December 15, 2026 and interim periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating the impact of this standard on our consolidated financial statements and related disclosures.