<?xml version="1.0" encoding="US-ASCII"?>
<!-- DFIN New ActiveDisclosure (SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date :2026-05-27T11:10:36.1813+00:00 -->
<!-- Copyright (c) 2026 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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        <link:definition>75050 - Disclosure - Investments in Master Trust</link:definition>
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        <link:definition>75070 - Disclosure - Risks and Uncertainties</link:definition>
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        <link:definition>75080 - Disclosure - Reconciliation of Financial Statements to Form 5500</link:definition>
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        <link:definition>75090 - Disclosure - Transactions with Parties-in-Interest and Related Parties</link:definition>
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        <link:definition>75110 - Disclosure - Significant Accounting Policies (Policies)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>75120 - Disclosure - Investments in Master Trust (Tables)</link:definition>
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        <link:definition>75130 - Disclosure - Reconciliation of Financial Statements to Form 5500 (Tables)</link:definition>
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        <link:definition>75140 - Disclosure - Schedule of Assets (Held at End of Year) (Tables)</link:definition>
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        <link:definition>75150 - Disclosure - Description of the Plan (Additional Information) (Details)</link:definition>
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        <link:definition>75160 - Disclosure - Investments in Master Trust (Additional Information) (Details)</link:definition>
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        <link:definition>75170 - Disclosure - Investments in Master Trust - Employee Benefit Plan, Schedule of Investments and Other Assets and Liabilities of The Master Trust and the Plan's Divided Interest in The Master Trust (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:definition>75180 - Disclosure - Investments in Master Trust - Employee Benefit Plan, Schedule of Net Investment Income for The Master Trust (Details)</link:definition>
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        <link:definition>75190 - Disclosure - Investments in Master Trust - Employee Benefit Plan, Schedule of Fair Value Hierarchy, the Master Trust's Assets (Details)</link:definition>
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        <link:definition>75200 - Disclosure - Tax Status (Additional Information) (Details)</link:definition>
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        <link:definition>75210 - Disclosure - Reconciliation of Financial Statements to Form 5500 - Employee Benefit Plan, Schedule of Reconciliation of Net Assets Available for Benefits Per The Financial Statements to Form 5500 (Details)</link:definition>
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        <link:definition>75220 - Disclosure - Reconciliation of Financial Statements to Form 5500 - Employee Benefit Plan, Schedule of Reconciliation of Net Increase Per The Financial Statements to Form 5500 (Details)</link:definition>
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        <link:definition>75230 - Schedule - Schedule of Assets (Held at End of Year) (Details)</link:definition>
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        <link:definition>75230 - Schedule - Schedule of Assets (Held at End of Year) (Details) [Default]</link:definition>
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        <link:definition>75240 - Disclosure - Transactions with Parties-in-Interest and Related Parties (Additional Information) (Details)</link:definition>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Forfeited Nonvested Account</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestIncomeOnNoteReceivableFromParticipant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest income from notes receivable from participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIdentifierAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Identifier [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Change in Net Asset Available for Benefit, Decrease from Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitDecreaseForAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Description of Plan [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanMasterTrustAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Master Trust [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Employer Contribution, Matching Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Percentage of Vested Contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentIssuerNameExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment, Issuer Name [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Accounting Policy [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanMasterTrustTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Master Trust [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Schedule of Asset Held for Investment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Statement of Net Asset Available for Benefit [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Form 5500 Caption, Benefit Payment and Payments to Provide Benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">EBP, Form 5500 Caption, Benefit Payment and Payments to Provide Benefits, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionPaymentToParticipant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total net increase per the Form 5500</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Amount of Borrowed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Collective Trust [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collective trust funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Company common stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Participant Contribution, Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contributions receivable From Participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Schedule of Asset Held for Investment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNonconsolidatedMasterTrustAndPlanInterestInMasterTrustDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Nonconsolidated, Master Trust and Plan Interest in Master Trust [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total Master Trust investments, at fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Master Trust assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanSelfDirectedBrokerageAccountMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Self-Directed Brokerage Account [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanSelfDirectedBrokerageAccountMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Self-directed brokerage accounts [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccountDecreaseForAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Forfeited Nonvested Account, Decrease from Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccountDecreaseForAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Administrative Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment Valuation and Income Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EbpSubsequentEventTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Subsequent Event [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Accounting Policy [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EbpSubsequentEventAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Subsequent Event [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanBasisOfAccountingPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Accounting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanBasisOfAccountingPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Basis of Accounting [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentPlanInterestInMasterTrustFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment, Plan Interest in Master Trust, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentPlanInterestInMasterTrustFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plan interest in Master Trust</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Description of Plan [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanPercentageOfInterestRatesOnLoansOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Benefit Plan, Percentage of Interest Rates on Loans Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanPercentageOfInterestRatesOnLoansOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Employee Benefit Plan, Percentage of Interest Rates on Loans Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanPercentageOfInterestRatesOnLoansOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan , Percentage of Interest Rates on Loans Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairAndContractValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment, Fair and Contract Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairAndContractValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Master Trust investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetAssetAvailableForBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Form 5500 Caption, Net Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanForm5500CaptionNetAssetAvailableForBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net assets available for benefits per the Form 5500</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transactions with Parties-in-Interest and Related Parties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Related Party and Party-in-Interest Transactions [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanNumberOfParticipantsLoans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Number of Participants Loans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanNumberOfParticipantsLoans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Benefit Plan, Number of Participants Loans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanNumberOfParticipantsLoans_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Employee Benefit Plan, Number of Participants Loans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Change in Net Asset Available for Benefit, Increase from Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanNetInvestmentIncomeForTheMasterTrustTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Net Investment Income for The Master Trust [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanNetInvestmentIncomeForTheMasterTrustTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Schedule of Net Investment Income for The Master Trust</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanNetInvestmentIncomeForTheMasterTrustTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Employee Benefit Plan, Net Investment Income for The Master Trust [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500LineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Reconciliation of Financial Statement to Form 5500 [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanOtherLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Other Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanOtherLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Administrative expenses payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanOtherLiability_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Administrative expenses payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measured at Net Asset Value Per Share [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Asset Value (NAV) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Statement of Net Asset Available for Benefit [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionExcludingRollover_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Excluding Rollover</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionExcludingRollover_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Participants Contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanTargetDateCollectiveFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Benefit Plan, Target Date Collective Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanTargetDateCollectiveFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">EBP, Target Date Collective Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanTargetDateCollectiveFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Target date collective funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Determination Letter Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanTaxDeterminationLetterDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Tax Determination Letter, Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Related Party and Party-in-Interest Transactions [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Amount of Plan Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanUseOfEstimatePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Use of Estimates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanUseOfEstimatePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Use of Estimate [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment, Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanSummaryOfAccountingPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Summary of Accounting Policy [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanSummaryOfAccountingPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Significant Accounting Policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Description of Plan and Accounting Change [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Reconciliation of Financial Statement to Form 5500 [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500TableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Schedule of Reconciliation of Net Assets Available for Benefits Per The Financial Statements to Form 5500</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Statement of Change in Net Asset Available for Benefit [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Note Receivable from Participant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes receivable from participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Risk and Uncertainty [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Note Receivable from Participant, Account, Maximum Borrowing, to Total Account, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Percenatge of Amount Borrowed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanRelatedPartyAndPartyInInterestTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Related Party and Party-in-Interest Transactions [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanSubsequentEventTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Subsequent Event [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanSubsequentEventTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestIncomeOnInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Change in Net Asset Available for Benefit, Increase from Interest Income on Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForInterestIncomeOnInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Annual Compensation Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Participant Contribution, Pretax, Maximum Annual Compensation, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentTypeCategorizationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Risk and Uncertainty [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanMasterTrustTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments in Master Trust</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanMasterTrustTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Master Trust [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Net Asset Available for Benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net assets available for benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning of year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">End of year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNetAssetAvailableForBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net assets available for benefits per the financial statements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Schedule of Fair Value Hierarchy, The Master Trust's Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanInvestmentFairValueAndNavTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Investment, Fair Value and NAV [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Schedule of Asset Held for Investment [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanReconciliationOfNetIncreasePerTheFinancialStatementsToForm5500TableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Benefit Plan, Reconciliation of Net Increase Per The Financial Statements to Form 5500 [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanReconciliationOfNetIncreasePerTheFinancialStatementsToForm5500TableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">EBP, Reconciliation of Net Increase Per The Financial Statements to Form 5500 [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EmployeeBenefitPlanReconciliationOfNetIncreasePerTheFinancialStatementsToForm5500TableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Schedule of Reconciliation of Net Increase Per The Financial Statements to Form 5500</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Notes Receivable from Participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Note Receivable from Participant [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Schedule of Asset Held for Investment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanScheduleOfAssetHeldForInvestmentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Assets (Held at End of Year)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfNetAssetAvailableForBenefitTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Statement of Net Asset Available for Benefit [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForGainLossOnInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Gain (Loss) on Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForGainLossOnInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Gain (Loss) on Investment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForGainLossOnInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net realized and unrealized appreciation in fair value of investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNonconsolidatedMasterTrustMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Nonconsolidated, Master Trust [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNonconsolidatedMasterTrustMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Master Trust Balances [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNonconsolidatedMasterTrustMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Master Trust [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Employer Contribution, Participant Compensation Matched, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Percenatge of Annual Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanStatementOfChangeInNetAssetAvailableForBenefitTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Statement of Change in Net Asset Available for Benefit [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500NetAssetAvailableForBenefitAllocationToWithdrawingParticipantNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Allocation to Withdrawing Participant, Not yet Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500NetAssetAvailableForBenefitAllocationToWithdrawingParticipantNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amounts allocated to withdrawn participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500NetAssetAvailableForBenefitAllocationToWithdrawingParticipantNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amounts allocated to withdrawn participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500NetAssetAvailableForBenefitAllocationToWithdrawingParticipantNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Amounts allocated to withdrawing participants at December 31,2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500NetAssetAvailableForBenefitAllocationToWithdrawingParticipantNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Amounts allocated to withdrawing participants at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500NetAssetAvailableForBenefitAllocationToWithdrawingParticipantNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodStartLabel">Amounts allocated to withdrawing participants at December 31,2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanReconciliationToForm5500NetAssetAvailableForBenefitAllocationToWithdrawingParticipantNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodEndLabel">Amounts allocated to withdrawing participants at December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanContributionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Contribution [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanContributionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanPlanNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Plan Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanPlanNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, PlanNumber</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNonconsolidatedPlanInterestInMasterTrustMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Nonconsolidated, Plan Interest in Master Trust [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanNonconsolidatedPlanInterestInMasterTrustMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plan's Divided Interest in Master Trust Balances [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LegalEntityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legal Entity [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EbpPlanName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Plan Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EbpPlanName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plan, Plan Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EbpRiskAndUncertaintyLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Risk and Uncertainty [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net investment income from Master Trust</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseDecreaseForIncomeLossOnInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net investment income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionRollover_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Rollover</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanChangeInNetAssetAvailableForBenefitIncreaseForParticipantContributionRollover_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rollover Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAccountingPolicyAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Accounting Policy, Accounting Standard Update, and Change in Accounting Principle [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Asset Held for Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EmployeeBenefitPlanAssetHeldForInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">EBP, Asset Held for Investment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap-ebp_EbpSubsequentEventLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP, Subsequent Event [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EBP002Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EBP 002 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="pkg_EBP002Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">EBP 002 [Member]</link:label>
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