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Stock, Cash Amendment Flag Amendment Flag Expected required contributions Defined Benefit Plan Estimated Required Future Employer Contributions In Current Fiscal Year Defined benefit plan estimated required future employer contributions in current fiscal year. 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Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Depreciation, Depletion and Amortization Depreciation, Depletion and Amortization Jul-23 [Member] Jul-25 [Member] Jul-25 Fair Value as of Grant Date Award Grant Date Fair Value Debt Disclosure [Text Block] Debt Disclosure [Text Block] Geographical [Domain] Geographical [Domain] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table Text Block] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date: Restatement Determination Date [Axis] Title of 12(b) Security Title of 12(b) Security Common stock, no par value (authorized shares 150,000,000, issued and outstanding 34,484,893 shares at June 30, 2024 and 34,408,638 shares at December 31, 2023) Common Stock, Value, Issued Proceeds from Sale of Other Assets, Investing Activities Proceeds from Sale of Other Assets, Investing Activities Revenue from Contract with Customer by Geographic Location [Abstract] Revenue from Contract with Customer by Geographic Location [Abstract] Revenue from Contract with Customer by Geographic Location [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Terphane Ltda [Member] Terphane Ltda [Member] Terphane Ltda [Member] Other Noncurrent Assets Other Noncurrent Assets [Member] Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Reclassification from AOCI, Current Period, Tax Reclassification from AOCI, Current Period, Tax Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Derivatives Designated As Hedging Instruments [Member] Designated as Hedging Instrument [Member] Current Effective Tax Rate Including Social Contribution On Income Current Effective Tax Rate Including Social Contribution On Income Current Effective Tax Rate Including Social Contribution On Income Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Total current liabilities Liabilities, Current Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Total assets Assets Assets Flexible Packaging Films [Member] [Domain] Flexible Packaging Films [Member] [Domain] Flexible Packaging Films [Member] [Domain] Share Based Compensation Expense, Value Share Based Compensation Expense, Value Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, stock options, restricted stock or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Cost of Goods and Services Sold Cost of Goods and Services Sold Common Stock, Shares Held in Employee Trust, Shares Common Stock, Shares Held in Employee Trust, Shares Income taxes recoverable Income Taxes Receivable, Current Capital expenditures Payments to Acquire Property, Plant, and Equipment Other non-current liabilities Other Liabilities, Noncurrent Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Interest expense Interest and Debt Expense Guangzhou Tredegar Loan Guangzhou Tredegar Loan [Member] Guangzhou Tredegar Loan Termination Date Trading Arrangement Termination Date Revenues Revenues Entity Address, City or Town Entity Address, City or Town Debt Instrument [Axis] Debt Instrument [Axis] Stock-based compensation expense Share-Based Payment Arrangement, Expense Net Income (Loss) Attributable to Parent, Total Net Income (Loss) Attributable to Parent Net Income (Loss) Net Income (Loss) Attributable to Parent Trading Arrangement: Trading Arrangement [Axis] Comprehensive Income (Loss) Note [Text Block] Comprehensive Income (Loss) Note [Text Block] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Aluminum Extrusions Subtotal [Member] Aluminum Extrusions Subtotal [Member] Aluminum Extrusions Subtotal [Member] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Entity File Number Entity File Number Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Document Fiscal Year Focus Document Fiscal Year Focus Income Statement [Abstract] Income Statement [Abstract] Entity Address, Address Line One Entity Address, Address Line One OCI, before Reclassifications, before Tax, Attributable to Parent OCI, before Reclassifications, before Tax, Attributable to Parent Commitment Under Cash Flow Hedges, Mass Commitment Under Cash Flow Hedges, Mass Commitment Under Cash Flow Hedges, Mass Trust For Saving Restoration Plan [Member] Trust For Saving Restoration Plan [Member] Trust For Saving Restoration Plan. Earnings before interest and taxes (EBIT) Earnings before interest and taxes (EBIT) Earnings before interest and taxes (EBIT) Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Effect of exchange rate changes on cash Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations Name Forgone Recovery, Individual Name Document Period End Date Document Period End Date Finished goods Inventory, Finished Goods, Net of Reserves Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Base Rate Base Rate [Member] Insider Trading Arrangements [Line Items] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Asset impairments and costs associated with exit and disposal activities, net of adjustments Asset Impairment And Costs Associated With Exit And Disposal Activities - impairment Line Amounts charged against earnings for incurred and estimated one-time, nonrecurring costs assoicated with asset impariments and exit and disposal activities. Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Diluted (in dollars per share) Income (Loss) from Continuing Operations, Per Diluted Share Adjustment to Compensation: Adjustment to Compensation [Axis] Prepaid expenses and other Prepaid Expense and Other Assets, Current Accrued Expenses [Member] Accrued Expenses [Member] Accrued Expenses [Member] Document Transition Report Document Transition Report Document Quarterly Report Document Quarterly Report Schedule Of Components Of Net Periodic Benefit Cost For Pension And Other Post-Retirement Benefit Programs Schedule Of Components Of Net Periodic Benefit Cost For Pension And Other Post-Retirement Benefit Programs [Table Text Block] Schedule Of Components Of Net Periodic Benefit Cost For Pension And Other Post-Retirement Benefit Programs [Table Text Block] Latin America [Member] Latin America [Member] Entity Current Reporting Status Entity Current Reporting Status Retained Earnings [Member] Retained Earnings [Member] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Basic (in shares) Weighted average shares outstanding used to compute basic earnings per share Weighted Average Number of Shares Outstanding, Basic Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] less than 33% of $125 million aggregate commitment less than 33% of $125 million aggregate commitment [Member] less than 33% of $125 million aggregate commitment Nonresidential Building And Construction [Member] Nonresidential Building And Construction [Member] Nonresidential Building And Construction [Member] Nature of Expense [Axis] Nature of Expense [Axis] Executive Category: Executive Category [Axis] Name Awards Close in Time to MNPI Disclosures, Individual Name Income Tax Beneficiary [Axis] Income Tax Beneficiary [Axis] Income Tax Beneficiary [Axis] Entity Filer Category Entity Filer Category Annual Net Costs Mismatch Translation Exposure - Real vs US Dollar Annual Net Costs Mismatch Translation Exposure - Real vs US Dollar Annual Net Costs Mismatch Translation Exposure - Real vs US Dollar Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Income Statement and Other Comprehensive Income (Loss) Location [Domain] Statement of Income Location, Balance [Domain] Costs and expenses: Cost of Revenue [Abstract] Company Selected Measure Name Company Selected Measure Name