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Accounts payable Increase (Decrease) in Accounts Payable Increase (Decrease) in Accounts Payable, Total Adjustment [Member] Revision of Prior Period, Adjustment [Member] Equity [Abstract] Amounts reclassified from AOCI, net of tax Amounts reclassified from AOCI, net of tax Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Granted Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Senior Notes Senior Notes [Member] Revision of Prior Period [Axis] Cash payments paid for interest Interest Paid, Including Capitalized Interest, Operating and Investing Activities Interest Paid, Including Capitalized Interest, Operating and Investing Activities, Total Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Equity Components Equity Components [Axis] Unrecognized Compensation Expense for Share-Based Awards Share-Based Payment Arrangement, Nonvested Award, Cost [Table Text Block] Accounts receivable Increase (Decrease) in Accounts Receivable Investments, Debt and Equity Securities [Abstract] Employee Benefit Plans and Other Postretirement Benefits Retirement Benefits [Text Block] Inventory Disclosure [Abstract] New Accounting Standards Accounting Standards Update and Change in Accounting Principle [Text Block] Depreciation [Abstract] Depreciation [Abstract] Components of Other Income (Expense) Schedule of Other Operating Cost and Expense, by Component [Table Text Block] Weighted Average Grant-Date Fair Value, Vested Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Local Phone Number Local Phone Number Property, Plant, And Equipment [Line Items] Property, Plant and Equipment [Line Items] Total Company Sales Revenue Net Sales Revenue Goods [Member] Net sales revenue goods. Office Depot Office Depot [Member] Office Depot. Goodwill Goodwill Goodwill, Total Goodwill, Beginning Balance Goodwill, Ending Balance Packaging Packaging [Member] Reportable segment - Packaging. Statement of Cash Flows [Abstract] Retirement Plan Tax Status Retirement Plan Tax Status [Axis] Packaging and Paper Packaging And Paper [Member] Packaging and paper. 3.05% Senior Notes Due October 2051 3.05% Senior Notes due in October 2051 [Member] 3.05% Senior Notes, due October 2051 Three Point Zero Five Percentage Senior Notes Due October Two Thousand And Fifty One [Member] Organization, Consolidation and Presentation of Financial Statements [Abstract] Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Income (Loss), Net of Tax, Total Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Gross profit Gross Profit Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Unrealized Loss On Foreign Exchange Contracts Payment of civil penalty Payment of civil penalty Payment of civil penalty Concentration Risk Benchmark Concentration Risk Benchmark [Axis] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Jackson, Alabama Mill Jackson Alabama Mill [Member] Jackson, Alabama mill. Numerator: Net Income (Loss) Available to Common Stockholders, Basic [Abstract] Interest expense, net Interest Income (Expense), Nonoperating, Net Debt Instrument, Interest Rate, Stated Percentage Stated interest rate Remaining weighted-average recognition period Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Long-Lived Tangible Asset Long-Lived Tangible Asset [Axis] Number of shares authorized under plan Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Maximum Maximum [Member] Consolidation Items Consolidation Items [Domain] Corrugated Products Facilities And Design Centres [Member] Corrugated Products Facilities And Design Centres [Member] Corrugated Products Facilities And Design Centres Accrued and unpaid interest Debt Instrument, Increase, Accrued Interest Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Domain] Share-based compensation and other APIC, Share-Based Payment Arrangement, Increase for Cost Recognition APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Total Net increase in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Service cost Defined Benefit Plan, Service Cost Payments for (Proceeds from) Other Investing Activities Other, net Effect of dilutive securities (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Incremental Common Shares Attributable to Share-based Payment Arrangements, Total Operating Segments Operating Segments [Member] Reporting Unit Reporting Unit [Axis] Components of Inventories Schedule of Inventory, Current [Table Text Block] Fiber Fiber [Member] Fiber [Member] Segment Information Segment Reporting Disclosure [Text Block] Facilities closure and other income (costs) Jackson mill conversion-related activities Business Exit And Other Costs Business exit and other costs. City Area Code City Area Code Components of Changes in Accumulated Other Comprehensive Income (AOCI) Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Inventories Inventories Inventory, Net Cash Flows from Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Consolidation Items Consolidation Items [Axis] Debt instrument, repurchase amount Debt Instrument, Repurchase Amount Letter of Credit [Member] Letter Of Credit Intangible Assets Intangible Assets, Current Intangible Assets, Current, Total Intangible assets Denominator: Weighted Average Number of Shares Outstanding, Basic [Abstract] Acquisitions Goodwill Revised During Period Goodwill revised during period. Customer Customer [Domain] Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Beginning Balance Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance Less accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Total Weighted average basic common shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Weighted Average Number of Shares Outstanding, Basic, Total Share-Based Payment Arrangement, Noncash Expense [Abstract] Work in process Inventory, Work in Process, Gross Cash Flows from Financing Activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Statement [Table] Statement [Table] Total Company Receivables Accounts Receivable Schedule Of Related Party Transactions By Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Document Fiscal Period Focus Document Fiscal Period Focus Total long-term liabilities Liabilities, Noncurrent Redemption premium Redemption Premium Transactions With Related Parties Related Party Transactions Disclosure [Text Block] Statement [Line Items] Statement [Line Items] Goodwill Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total Financing costs paid Payments of Financing Costs Payments of Financing Costs, Total Schedule of Long-Term Debt Instruments [Table Text Block] Summary of Debt Machinery and Equipment Machinery and Equipment [Member] Subsequent Event [Line Items] Date of incorporation Entity Incorporation, Date of Incorporation Accounts receivable, net of allowance for credit losses and customer deductions of $12.1 million and $13.1 million as of March 31, 2024 and December 31, 2023, respectively Accounts receivable, net, current Accounts Receivable, after Allowance for Credit Loss, Current Accounts Receivable, after Allowance for Credit Loss, Current, Total Customer Customer [Axis] Trade Names Trade names Trade names Common Stock Common Stock [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Cash and Cash Equivalents, at Carrying Value, Total Cash and Cash Equivalents, at Carrying Value, Beginning Balance Cash and Cash Equivalents, at Carrying Value, Ending Balance Marketable Debt Loss Position Fair Value Marketable Debt Loss Position Fair Value Marketable debt loss position fair value. Buildings Building [Member] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding DeRidder, Louisiana De Ridder Louisiana [Member] DeRidder, Louisiana. Proceeds from sales of available-for-sale debt securities Proceeds from Sale of Debt Securities, Available-for-Sale Liability insurance Loss Contingency Accrual Loss Contingency Accrual, Beginning Balance Loss Contingency Accrual, Ending Balance Property, plant and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total Finished goods Inventory, Finished Goods, Gross Inventory, Finished Goods, Gross, Total Write off amount of remaining balance of unamortized debt issuance costs Deferred Debt Issuance Cost, Writeoff Other Other Operating Income (Expense), Net Less: Distributed and undistributed earnings allocated to participating securities Participating Securities, Distributed and Undistributed Earnings (Loss), Basic Cover [Abstract] Selling, general and administrative expenses Selling, General and Administrative Expense Selling, General and Administrative Expense, Total Percentage of nondeductible excise tax Percentage of nondeductible excise tax Percentage of nondeductible excise tax Document Fiscal Year Focus Document Fiscal Year Focus DeRidder litigation DeRidder litigation Payments for Legal Settlements Damage compensation to plaintiff Loss Contingency Accrual, Payments Cash paid for taxes, net of refunds received Income Taxes Paid, Net Income Taxes Paid, Net, Total Accrued interest Interest Payable, Current Federal and state income taxes receivable Income Taxes Receivable, Current Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification out of Accumulated Other Comprehensive Income [Member] Share-based compensation and other (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, before Forfeiture Weighted Average Grant-Date Fair Value, Granted Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Restructuring Plan Restructuring Plan [Domain] Segment Reporting [Abstract] Proceeds from asset disposals Proceeds from Sale of Productive Assets Proceeds from Sale of Productive Assets, Total DeRidder Louisiana Mill [Member] DeRidder louisiana mill. Security Exchange Name Security Exchange Name Other comprehensive income Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Other comprehensive income New Accounting Pronouncements, Policy [Policy Text Block] Recently Adopted Accounting Standards Total Other expense, net Operating Costs and Expenses Operating Costs and Expenses, Total Customer Relationships Customer Relationships [Member] Schedule Of Finite Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Property, plant and equipment, at cost Property, Plant and Equipment, Gross Property, Plant and Equipment, Gross, Total Property, Plant and Equipment, Gross, Beginning Balance Property, Plant and Equipment, Gross, Ending Balance New accounting standards not yet adopted. New Accounting Standards Not Yet Adopted Policy [Text Block] New Accounting Standards Not Yet Adopted Business Acquisition, Acquiree [Domain] Legal Entity Legal Entity [Axis] Financial Instrument Financial Instrument [Axis] Compensation and benefits Accrued Employee Benefits, Current Payments for proceeds from seller, Payments For Proceeds From Seller Payments for proceeds from seller Entity Emerging Growth Company Entity Emerging Growth Company Amendment Flag Amendment Flag Investment in debt security held-to-maturity Debt Securities, Held-to-Maturity, Fair Value Debt Securities, Held-to-Maturity, Fair Value, Total Components of Accrued Liabilities Schedule of Accrued Liabilities [Table Text Block] Customer rebates and other credits Accrued Marketing Costs, Current DeRidder Litigation DeRidder Litigation Debt Refinancing Cost Debt Refinancing Cost Debt Refinancing Cost Short-term marketable debt securities Short-Term Marketable Debt Securities Short-Term Marketable Debt Securities DeRidder litigation insurance recovery Proceeds from Legal Settlements Paper Paper [Member] Reportable segment - Paper. Fair Value of Marketable Debt Securities Debt Securities, Available-for-Sale, Unrealized Loss Position Debt Securities, Available-for-sale, Unrealized Loss Position, Total Entity File Number Securities Act File Number Series of Individually Immaterial Business Acquisitions [Member] Series of Individually Immaterial Business Acquisitions [Member] Goodwill and Intangible Assets Disclosure [Abstract] Time Deposits Bank Time Deposits [Member] Long-term debt Long-Term Debt, Excluding Current Maturities Long-term Debt, Excluding Current Maturities, Total Total Long term debt Changes in unrealized (losses) gains on marketable debt securities, net of tax of $0.0 million and ($0.2) million for 2024 and 2023, respectively Changes in unrealized (losses) gains on marketable debt securities, net of tax of $0.0 million and ($0.2) million for 2024 and 2023, respectively OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Acquisitions Asset Acquisition [Text Block] Percentage of ROIC as performance measure Share Based Compensation Arrangement By Share Based Payment Award Percentage Of Performance Measurement Based On Return On Invested Capital Share based compensation arrangement by share based payment award percentage of performance measurement based on return on invested capital. Common stock dividends declared Dividends, Common Stock, Cash Accounts payable Accounts Payable, Current Accounts Payable, Current, Total Debt Instrument Debt Instrument [Axis] Cash, Cash Equivalents, and Marketable Debt Securities Cash, Cash Equivalents, and Marketable Securities [Text Block] Weighted Average Grant-Date Fair Value, Outstanding at January 1, 2024 Weighted Average Grant-Date Fair Value, Outstanding at March 31, 2024 Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Other Intangible Assets Other Intangible Assets, Net Other intangibles Boise Cascade Co-Owner of LTP Co-venturer [Member] Variable Interest Entity Variable Interest Entity, Primary Beneficiary [Member] Long-term marketable debt securities Long-term marketable debt securities Debt Securities, Available-for-Sale, Noncurrent Schedule Of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Variable interest entity, ownership percentage Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage Entity Small Business Entity Small Business Entity Shell Company Entity Shell Company (Increase) decrease in assets - Increase (Decrease) in Operating Assets [Abstract] Summary of Restricted Stock and Performance Unit Award Activity Schedule of Nonvested Share Activity [Table Text Block] Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component Non-operating pension income Non-operating pension (expense) income Pension and post-retirement benefits expense, net of contributions Pension And Postretirement Benefits Contributions Expense Net The amount of pension and postretirement benefit costs recognized during the period, less the amount of contributions made by the entity to fund its plans. For defined benefit plans, pension and postretirement expense includes the following components: service cost, interest cost, expected return on plan assets, gain or loss on plan assets, prior service cost or credit, transition asset or obligation, and gain or loss due to settlements or curtailments. Long-term liabilities: Liabilities, Noncurrent [Abstract] Restricted Stock and Performance Units (Weighted Average Grant-date Fair Value) [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Certificates of Deposit Certificates of Deposit [Member] Earnings Per Share Earnings Per Share [Text Block] Trademarks and Trade Names Trademarks and Trade Names [Member] Entity Address, Address Line One Entity Address, Address Line One Finite-Lived Intangible Assets, Period Increase (Decrease) Finite-Lived Intangible Assets, Period Increase (Decrease), Total Adjustment to decrease the remaining book value of intangible asset Adjustments to intangible assets valuation Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Other intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill, Total Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Gross Carrying Amount Finite-Lived Intangible Assets, Gross Finite-Lived Intangible Assets, Gross, Total Subsequent Event Type Subsequent Event Type [Domain] Incremental out-of-pocket costs Incremental Out Of Pocket Costs Incremental out of pocket costs. Impairment of marketable debt securities Impairment Of Marketable Debt Securities Impairment of marketable debt securities. Long-term Debt, Type Long-Term Debt, Type [Axis] Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total Level 2 Fair Value, Inputs, Level 2 [Member] Product and Service Product and Service [Axis] Title of 12(b) Security Title of 12(b) Security Additions to other long term assets Payments to Acquire Other Productive Assets Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization COVID nineteen. Covid Nineteen [Member] COVID-19 Components of Intangible Assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Compensatory damage Loss Contingency, Damages Awarded, Value Other net assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Foreign Exchange Contract [Member] Foreign Exchange Contract Cash Flows from Investing Activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Amortization of financing costs Amortization of Debt Issuance Costs Goodwill impairment charge Goodwill, Impairment Loss Goodwill impairment Goodwill impairment Concentration Risk [Table] Concentration Risk [Table] Long-Lived Tangible Asset Long-Lived Tangible Asset [Domain] Other comprehensive income before reclassifications, net of tax OCI, before Reclassifications, Net of Tax, Attributable to Parent Subsequent Event [Table] Dividends declared per common share Common Stock, Dividends, Per Share, Declared Increase (Decrease) in Inventories Inventories Increase (Decrease) in Inventories, Total Fiber costs from related parties Related Parties Amount in Cost of Sales Other, net Other Operating Activities, Cash Flow Statement Unrealized Losses Unrealized Losses Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total Franchise, property, sales and use taxes Accrual For Franchise Property Sales And Use Taxes Current Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes, sales and use taxes, and franchise taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Repurchases of common stock under stock repurchase program Stock Repurchase Program, Remaining Authorized Repurchase Amount Restructuring Plan Restructuring Plan [Axis] Share-Based Compensation Share-Based Payment Arrangement [Text Block] Weighted Average Grant-Date Fair Value, Forfeitures Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Payment of penalties Payment Of Penalties Payment of penalties. Three Point Four Percentage Senior Notes Due December Two Thousand And Twenty Seven [Member] Three point four percentage senior notes due december two thousand and twenty seven. Unrealized Gain Unrealized Gain On Securities1 Unrealized gain on securities 1. Repurchases of common stock under stock repurchase program Repurchases Of Common Stock Under Stock Repurchase Program Repurchases of common stock under stock repurchase program. Retirement Plan Type Retirement Plan Type [Axis] Concentration Risk Type Concentration Risk Type [Domain] Asset Acquisition [Abstract] Document Type Document Type Amortization of prior service costs Net amortization of unrecognized amounts, Prior service cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Line of Credit [Member] Net cash used for investing activities Net Cash Provided by (Used in) Investing Activities Document Quarterly Report Document Quarterly Report Components of Net Periodic Benefit Costs Schedule of Net Benefit Costs [Table Text Block] Counterparty Name [Domain] Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Loss contingency, period of occurrence Loss Contingency, Period of Occurrence Net income attributable to common shareholders Net Income (Loss) Available to Common Stockholders, Basic Forfeitures Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Net Cash Provided by (Used in) Financing Activities Net cash used for financing activities Entity Filer Category Entity Filer Category Qualified Plan Qualified Plan [Member] Debt Instrument, Periodic Payment, Interest Debt instrument interest Accrued liabilities Increase (Decrease) in Accrued Liabilities Increase (Decrease) in Accrued Liabilities, Total Accrued Liabilities, Current [Abstract] Purchases of available-for-sale debt securities Payments to Acquire Marketable Securities Payments to Acquire Marketable Securities, Total Intersegment Intersegment [Member] Intersegment. Purchases of property, plant, and equipment included in accounts payable Capital Expenditures Incurred but Not yet Paid Carrying amount of LTP's liabilities Liabilities Liabilities, Total Schedule Of Property Plant And Equipment [Table] Property, Plant and Equipment [Table] Recoverability test results recoverable percentage Recoverability Test Results Recoverable Percentage Recoverability test results recoverable percentage. Schedule Of Commitments And Contingencies [Line Items] Schedule Of Commitments And Contingencies [Line Items] Schedule of commitments and contingencies. Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions Number of Marketable Debt Securities in a Loss Position 12 Months Or Longer Weighted Average Remaining Useful Life (in Years) Finite-Lived Intangible Asset, Useful Life Accumulated Other Comprehensive Income Loss [Table] Accumulated Other Comprehensive Income (Loss) [Table] Total stockholders' equity Beginning balance Ending balance Equity, Attributable to Parent Weighted average useful life of intangible asset acquired Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life Accrued Liabilities [Abstract] Consolidated Entities Consolidated Entities [Axis] Net income Corporate Debt Securities Corporate Debt Securities [Member] Statement of Financial Position [Abstract] Weighted average diluted common shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Increase (decrease) in liabilities - Increase (Decrease) in Operating Liabilities [Abstract] Hurricane Laura [Member] Hurricane laura. Effective income tax rate, percent Effective Income Tax Rate Reconciliation, Percent Effective Income Tax Rate Reconciliation, Percent, Total Other Income and Expenses [Abstract] Payments to acquire assets Payments to Acquire Productive Assets Payments to Acquire Productive Assets, Total Medical insurance and workers’ compensation Accrued Medical Insurance And Workers Compensation Current Accrued medical insurance and workers compensation current. Net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Income Taxes Income Tax Disclosure [Text Block] Net assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Finite Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Computation of Basic and Diluted Income Per Common Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Disaggregation Of Revenue [Line Items] Disaggregation of Revenue [Line Items] Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Unrealized Losses 12 Months Or Longer Unrealized Losses 12 Months Or Longer Schedule of Tangible and Intangible Assets Acquired and Liabilities Assumed Schedule of Business Acquisitions, by Acquisition [Table Text Block] Fair Value Hierarchy and NAV Fair Value Hierarchy and NAV [Axis] Additions to property, plant, and equipment Payments to Acquire Property, Plant, and Equipment Payments to Acquire Property, Plant, and Equipment, Total Revision of Prior Period [Domain] Vested Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Business Acquisition [Axis] Cash and cash equivalents, end of period Cash and cash equivalents, beginning of period Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Total Goodwill, Period Increase (Decrease), Total Goodwill, Period Increase (Decrease) Decrease in Goodwill Accounting Standards Update and Change in Accounting Principle [Abstract] Income Tax Disclosure [Abstract] Finite-Lived Intangible Assets by Major Class Finite-Lived Intangible Assets by Major Class [Axis] Packaging Corporation of America Packaging Corporation Of America [Member] Packaging Corporation of America [Member]