Total revenues, net of other expenses Total Revenues Net Of Other Expenses Total sales, net of returns, allowances and discounts, plus other non-operating income and expenses. Deferred Income Tax Assets, Net Deferred Income Tax Assets, Net Entity Address, Postal Zip Code Entity Address, Postal Zip Code Dividends paid Payments of Ordinary Dividends, Common Stock Property, plant and equipment, at cost Property, Plant and Equipment, Gross Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Proceeds from Sale of Other Assets, Investing Activities Proceeds from Sale of Other Assets, Investing Activities Total Segment Income (Loss) Total Income Loss Associated With Segments Total income and loss before income expenses associated with a specific segment. Includes income/loss from ongoing operations; plant shutdowns, asset impairments, restructurings and other non-recurring charges; and goodwill impairment charges. Inventory, Net [Abstract] Inventory, Net [Abstract] May-23 Nov-22 [Member] Nov-22 Aluminum Extrusions [Member] Aluminum Extrusions [Member] Aluminum Extrusions Member. Credit Spread Over London Interbank Offered Rate Basis Points Credit Spread Over Secured Overnight Financing Rate Basis Points Credit spread over SOFR basis points. Other Income and Expenses [Abstract] Other Income and Expenses [Abstract] Effective income tax rate reconciliation social contribution on income Effective income tax rate reconciliation social contribution on income Effective income tax rate reconciliation social contribution on income. Income (loss) from discontinued operations, net of tax Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax Schedule of Other Nonoperating Income (Expense) [Table Text Block] Schedule of Other Nonoperating Income (Expense) [Table Text Block] Oct-23 Apr-23 [Member] Apr-23 Depreciation Depreciation General Corporate General Corporate [Member] General Corporate [Member] Aluminum Futures Contracts Aluminum Futures Contracts [Member] Aluminum futures contracts. Long-Lived Assets Long-Lived Assets Net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Dec-22 Jun-24 [Member] Jun-24 Accounts Receivable, before Allowance for Credit Loss Accounts Receivable, before Allowance for Credit Loss Foreign Currency Exchange Rate, Translation Foreign Currency Exchange Rate, Translation Net income (loss) Net Income (Loss) Attributable to Parent Net income (loss) Net Income (Loss) Attributable to Parent Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Other Receivables, Gross, Current Other Receivables, Gross, Current Tredegar common stock purchased by trust for savings restoration plan Tredegar Common Stock Purchased by Trust for Savings Restoration Plan Tredegar Common Stock Purchased By Trust For Savings Restoration Plan Accounts Receivable, before Allowance for Credit Loss, Current Accounts Receivable, before Allowance for Credit Loss, Current Equity Component [Domain] Equity Component [Domain] Schedule Of Identifiable Assets By Segment Schedule Of Identifiable Assets By Segment [Table Text Block] Schedule of identifiable assets by segment. Deferred income taxes Increase Decrease In Net Deferred Taxes Increase decrease in net deferred taxes. 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Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Entity Emerging Growth Company Entity Emerging Growth Company Raw materials Inventory, Raw Materials, Net of Reserves Line Of Credit Facility, Covenant Terms, Maximum Aggregate Dividends Line Of Credit Facility, Covenant Terms, Maximum Aggregate Dividends Line of credit facility, covenant terms, maximum aggregate dividends. Discontinued operations (in USD per share) Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share Income tax (expense) benefit Other Comprehensive Income (Loss) before Reclassifications, Tax Brazil BRAZIL Sales Net Sales Aggregrate revenue during the period from the sales of goods in the normal course of business, after deducting returns, allowances, discounts, and charges for outbound freight. 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Statement [Table] Statement [Table] Disposal Groups, Including Discontinued Operations Disposal Groups, Including Discontinued Operations [Table Text Block] Shares used to compute earnings (loss) per share: Shares Used To Compute Earnings Loss Per Share [Abstract] Shares Used To Compute Earnings Loss Per Share. 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restoration plan (111,861 shares at September 30, 2022 and 108,433 shares at December 31, 2021) Common Stock Held in Trust Equity Components [Axis] Equity Components [Axis] Film Products Subtotal [Member] Film Products Subtotal [Member] Film Products Subtotal [Member] May-24 Nov-23 [Member] Nov-23 Proceeds from Sale of Investment Projects Proceeds from Sale of Investment Projects Document Fiscal Year Focus Document Fiscal Year Focus Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Statement [Line Items] Statement [Line Items] Disposal Group, Including Discontinued Operation, Consideration Disposal Group, Including Discontinued Operation, Consideration Selling, general and administrative Selling, General and Administrative Expense Apr-23 Oct-22 [Member] Oct-22 Product [Member] Product [Member] Right-of-use leased assets Operating Lease, Right-of-Use Asset Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent 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Security Exchange Name Security Exchange Name Stock option-based compensation costs Stock or Unit Option Plan Expense Accounts and other receivables, net Accounts Receivable, after Allowance for Credit Loss Derivative, Notional Amount Derivative, Notional Amount Nov-23 May-23 [Member] May-23 Current assets of discontinued operations Disposal Group, Including Discontinued Operation, Assets, Current Indebtedness To Adjusted Ebitda Ratio Greater Than Three Point Five But Less Than Or Equal To Four [Member] Indebtedness To Adjusted Ebitda Ratio Greater Than Three Point Five [Member] Indebtedness To Adjusted Ebitda Ratio Greater Than Three Point Five Service cost Defined Benefit Plan, Service Cost Cover [Abstract] Accounts Receivable, Allowance for Credit Loss Accounts Receivable, Allowance for Credit Loss 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] Segment Reporting [Abstract] Segment Reporting [Abstract] Terphane Ltda [Member] Terphane Ltda [Member] Terphane Ltda [Member] Nov-22 May-24 [Member] May-24 Accounts and Other Receivables Financing Receivables [Text Block] Total liabilities and shareholders’ equity Liabilities and Equity Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Brazil One-time Tax Credit PIS/COFINS Brazil One-time Tax Credit PIS/COFINS Brazil One-time Tax Credit PIS/COFINS Debt principal payments Repayments of Long-Term Lines of Credit Investment Income, Dividend Investment Income, Dividend Incremental dilutive shares attributable to stock options and restricted stock Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Diluted: Earnings Per Share, Diluted [Abstract] Current Fiscal Year End Date Current Fiscal Year End Date Disposal Group, Including Discontinued Operation, Assets Disposal Group, Including Discontinued Operation, Assets Earnings Per Share, Diluted Earnings Per Share, Diluted Identifiable intangible assets, net Intangible Assets, Net (Excluding Goodwill) Cost Method Investments, Original Cost Cost Method Investments, Original Cost Accrued pension and post-retirement benefits Pension and Other Postretirement Benefits Cost (Reversal of Cost) Disposal Group, Including Discontinued Operation, General and Administrative Expense Disposal Group, Including Discontinued Operation, General and Administrative Expense 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 Total current liabilities Liabilities, Current Disposal Group, Including Discontinued Operation, adjustment to fair value Disposal Group, Including Discontinued Operation, adjustment to fair value Disposal Group, Including Discontinued Operation, adjustment to fair value Flexible Packaging Films [Member] [Domain] Flexible Packaging Films [Member] [Domain] Flexible Packaging Films [Member] [Domain] Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Stock-based compensation expense 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. Divestitures and Assets Held for Sale Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Derivative, Description of Hedged Item Schedule of Derivative Instruments [Table Text Block] Other Nonoperating Income (Expense), Net - Other Other Nonoperating Income (Expense), Net - Other Other Nonoperating Income (Expense), Net - Other Derivative Asset, Fair Value, Gross Asset Derivative Asset, Subject to Master Netting Arrangement, before Offset Income taxes recoverable/payable Increase (Decrease) in Income Taxes Payable, Net of Income Taxes Receivable Entity Address, Address Line One Entity Address, Address Line One Income Tax Authority [Domain] Income Tax Authority [Domain] Other Proceeds from (Payments for) Other Financing Activities Gain on investment in kaléo Unrealized Gain (Loss) on Investments Product and Service [Axis] Product and Service [Axis] Europe [Member] Europe [Member] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Pension and other postretirement benefit obligations, net Liability, Pension and Other Postretirement and Postemployment Benefits, Noncurrent Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Credit Facility [Axis] Credit Facility [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Inventories Inventory Disclosure [Text Block] Entity Tax Identification Number Entity Tax Identification Number Aluminum Extrusions Subtotal [Member] Aluminum Extrusions Subtotal [Member] Aluminum Extrusions Subtotal [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Schedule of Investments [Table] Schedule of Investments [Table] Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax Amortization of prior service costs and net gains or losses Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax Indebtedness To Adjusted Ebitda Ratio Greater Than Two But Less Than Or Equal To Three [Member] Indebtedness To Adjusted Ebitda Ratio Greater Than Two But Less Than Or Equal To Three [Member] Indebtedness-To-Adjusted EBITDA Ratio Greater Than Two But Less Than Or Equal To Three [Member] Other Noncurrent Assets Other Noncurrent Assets [Member] Credit Facility covenant maximum liquidity Credit Facility covenant maximum liquidity Credit Facility covenant maximum liquidity Commitment Under Cash Flow Hedges, Mass Commitment Under Cash Flow Hedges, Mass Commitment Under Cash Flow Hedges, Mass Trust for Savings Restoration Plan 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) Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table Text Block] Indebtedness To Adjusted Ebitda Ratio Greater Than One But Less Than Or Equal To Two [Member] Indebtedness To Adjusted Ebitda Ratio Greater Than One But Less Than Or Equal To Two [Member] Indebtedness-To-Adjusted EBITDA Ratio Greater Than One But Less Than Or Equal To Two [Member] Disposal Group, Including Discontinued Operation, Other Accrued Expense Disposal Group, Including Discontinued Operation, Other Accrued Expense Disposal Group, Including Discontinued Operation, Other Accrued Expense Asia [Member] Asia [Member] Increase (decrease) in cash & cash equivalents Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Line of credit facility, covenant terms, maximum debt to EBITDA ratio Line of credit facility, covenant terms, maximum debt to EBITDA ratio Line of credit facility, covenant terms, maximum debt to EBITDA ratio 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. Entity Central Index Key Entity Central Index Key Interest income Investment Income, Interest Latin America [Member] Latin America [Member] Disposal Group Including Discontinued Operation Cash Proceeds Disposal Group Including Discontinued Operation Cash Proceeds Disposal Group Including Discontinued Operation Cash Proceeds Entity [Domain] Entity [Domain] Accrued Expenses [Member] Accrued Expenses [Member] Accrued Expenses [Member] City Area Code City Area Code Assets Assets [Abstract] 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] Retirement Benefits [Abstract] Retirement Benefits [Abstract] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Other non-current liabilities Other Liabilities, Noncurrent Nonresidential Building And Construction [Member] Nonresidential Building And Construction [Member] Nonresidential Building And Construction [Member] Disposal Group, Including Discontinued Operation, Other Receivable Disposal Group, Including Discontinued Operation, Other Receivable Disposal Group, Including Discontinued Operation, Other Receivable Capital expenditures Payments to Acquire Property, Plant, and Equipment Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Foreign currency translation adjustment, tax (benefit) Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Cost of goods sold Cost of Sales [Member] Lease liability Short-Term Lease Payments Income Tax Beneficiary [Axis] Income Tax Beneficiary [Axis] Income Tax Beneficiary [Axis] 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 Other Post-Retirement Benefits Other Postretirement Benefits Plan [Member]