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          <link:loc xlink:type="locator" xlink:href="psn-20260331.xsd#psn_NumeratorForBasicsAndDilutedEpsAbstract" xlink:label="psn_NumeratorForBasicsAndDilutedEpsAbstract"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="us-gaap_AccountingPoliciesAbstract"/>
          <link:loc xlink:type="locator" xlink:href="psn-20260331.xsd#psn_FinanceLeasesOtherAssetsNoncurrent" xlink:label="psn_FinanceLeasesOtherAssetsNoncurrent"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleThresholdTradingDays" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdTradingDays"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems" xlink:label="us-gaap_DisaggregationOfRevenueLineItems"/>
          <link:loc xlink:type="locator" xlink:href="psn-20260331.xsd#psn_ScheduleOfNumeratorAndDenominatorUsedToComputeBasicAndDilutedEarningsPerShareTableTextBlock" xlink:label="psn_ScheduleOfNumeratorAndDenominatorUsedToComputeBasicAndDilutedEarningsPerShareTableTextBlock"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
          <link:loc xlink:type="locator" xlink:href="psn-20260331.xsd#psn_AccumulatedOtherComprehensiveIncomeEquityAccountsReceivable" xlink:label="psn_AccumulatedOtherComprehensiveIncomeEquityAccountsReceivable"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherPostretirementBenefitsExpenseReversalOfExpenseNoncash" xlink:label="us-gaap_OtherPostretirementBenefitsExpenseReversalOfExpenseNoncash"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour"/>
          <link:loc xlink:type="locator" xlink:href="psn-20260331.xsd#psn_RepaymentOfPrincipalAmountOfOurConvertibleSeniorNotes" xlink:label="psn_RepaymentOfPrincipalAmountOfOurConvertibleSeniorNotes"/>
          <link:loc xlink:type="locator" xlink:href="psn-20260331.xsd#psn_ScheduleOfFinancialInformationOfConsolidatedJointVenturesTableTextBlock" xlink:label="psn_ScheduleOfFinancialInformationOfConsolidatedJointVenturesTableTextBlock"/>
          <link:loc xlink:type="locator" xlink:href="psn-20260331.xsd#psn_OtherReconciliationFromNetIncomeToAdjustedEBITDA" xlink:label="psn_OtherReconciliationFromNetIncomeToAdjustedEBITDA"/>
          <link:loc xlink:type="locator" xlink:href="psn-20260331.xsd#psn_AccountingStandardsUpdate2024-04Member" xlink:label="psn_AccountingStandardsUpdate2024-04Member"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany" xlink:label="dei_EntityEmergingGrowthCompany"/>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationAcquisitionRelatedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisition related expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationAcquisitionRelatedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Acquisition-Related Cost, Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AccumulatedOtherComprehensiveIncomeEquityLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AccumulatedOtherComprehensiveIncomeEquityLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income Equity Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AccumulatedOtherComprehensiveIncomeEquityLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accumulated other comprehensive income equity liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPSharesInESOP_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Employee Stock Ownership Plan (ESOP), Shares in ESOP, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPSharesInESOP_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Company's stock held by ESOP</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPSharesInESOP_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock Ownership Plan (ESOP), Shares in ESOP</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Finance Lease, Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total present value of lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAdjustmentToRevenueImpactOfChangesInEstimatedClaimsOrIncentivesOverThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract with customer adjustment to revenue impact of changes in estimated claims or incentives over threshold.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAdjustmentToRevenueImpactOfChangesInEstimatedClaimsOrIncentivesOverThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract With Customer Adjustment To Revenue Impact Of Changes In Estimated Claims Or Incentives Over Threshold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAdjustmentToRevenueImpactOfChangesInEstimatedClaimsOrIncentivesOverThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impact of changes in estimated claims or incentives on revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, to be Paid, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfBondHedgeAndWarrantTransactionsIncreasedConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of bond hedge and warrant transactions increased conversion price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfBondHedgeAndWarrantTransactionsIncreasedConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Bond Hedge And Warrant Transactions Increased Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfBondHedgeAndWarrantTransactionsIncreasedConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of bond hedge and warrant transactions increased conversion price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Accounts Payable, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Long-Term Debt, Excluding Current Maturities, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Excluding Current Maturities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Change in Contingent Consideration, Liability, Increase (Decrease)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of contingent consideration to be achieved</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DefenseAndIntelligenceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defense And Intelligence</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DefenseAndIntelligenceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defense And Intelligence [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DefenseAndIntelligenceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defense and intelligence.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Dilutive effect of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plan Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill deductible for tax purposes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Goodwill, Expected Tax Deductible, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesLongTermLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Long-term lease liabilities, operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesLongTermLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Operating Leases Long Term Lease Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesLongTermLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination recognized identifiable assets acquired and liabilities assumed operating leases long-term lease liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfCashFlowInformationRelatedToLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Supplemental Cash Flow Information Related to Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfCashFlowInformationRelatedToLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Cash Flow Information Related To Leases Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfCashFlowInformationRelatedToLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of cash flow information related to leases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentIssuanceDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt issuance date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentIssuanceDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Issuance Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleConsecutiveBusinessDayPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Consecutive trading day period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleConsecutiveBusinessDayPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Consecutive Business Day Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleConsecutiveBusinessDayPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument convertible consecutive business day period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 2</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 2 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CommonStockSharesOutstandingIncludingEmployeeStockOwnershipPlanShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock shares outstanding including ESOP</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CommonStockSharesOutstandingIncludingEmployeeStockOwnershipPlanShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock Shares Outstanding Including Employee Stock Ownership Plan Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CommonStockSharesOutstandingIncludingEmployeeStockOwnershipPlanShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common stock shares outstanding including employee stock ownership plan shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerBasisOfPricingDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract with Customer, Basis of Pricing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerBasisOfPricingDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Basis of Pricing [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DelayedDrawTermLoanDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Delayed Draw Term Loan Due 2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DelayedDrawTermLoanDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Delayed Draw Term Loan Due Two Thousand Twenty Eight [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DelayedDrawTermLoanDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Delayed draw term loan due two thousand twenty eight.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, to be Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Stated Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202309Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update 2023-09 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202309Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2023-09</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AllegedViolationOfFalseClaimsActMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Alleged Violation of False Claims, Act</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AllegedViolationOfFalseClaimsActMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Alleged Violation Of False Claims Act [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AllegedViolationOfFalseClaimsActMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Alleged Violation Of False Claims Act.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EngineeredSystemsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Engineered Systems</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EngineeredSystemsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Engineered Systems [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EngineeredSystemsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Engineered systems.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Senior Notes due 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash and Cash Equivalents, at Carrying Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents (including $90,488 and $153,144 Cash of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Distributions to noncontrolling interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConnectedCommunitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Connected Communities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConnectedCommunitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Connected Communities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConnectedCommunitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Connected Communities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares, issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use assets obtained in exchange for new operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-of-Use Asset Obtained in Exchange for Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseOptionToTerminate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease option to terminate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseOptionToTerminate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Lease Option To Terminate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseOptionToTerminate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee lease option to terminate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountPaidPerMonthToContractorDefendantByRelatorOnFalseClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount paid per month to contractor defendant by relator on false claims</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountPaidPerMonthToContractorDefendantByRelatorOnFalseClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amount Paid Per Month To Contractor Defendant By Relator On False Claims</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountPaidPerMonthToContractorDefendantByRelatorOnFalseClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount paid per month to contractor defendant by relator on false claims.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">pre-judgment interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid to acquire</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Businesses, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash paid at closing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Debt, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance and sale of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EquityBasedCompensationIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EquityBasedCompensationIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Based Compensation Income Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EquityBasedCompensationIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Equity-based compensation income (expense).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Acquisition, Acquiree</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_InvesteesOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unconsolidated Joint Ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_InvesteesOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investees Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_InvesteesOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Investees Other.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">AOCI DEFERRED TAXES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities and shareholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Current Maturities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Long-Term Debt, Current Maturities, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Short-Term Debt:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Lived Tangible Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, to be Paid, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, frequency of periodic payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Frequency of Periodic Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BilledReceivablesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Billed Receivables Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BilledReceivablesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Billed receivables current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BilledReceivablesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Billed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentExerciseOfOptionByInitialPurchasersAggregatePrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of option by initial purchasers aggregate principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentExerciseOfOptionByInitialPurchasersAggregatePrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Exercise Of Option By Initial Purchasers Aggregate Principal Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentExerciseOfOptionByInitialPurchasersAggregatePrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument exercise of option by initial purchasers aggregate principal amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, by Balance Sheet Grouping [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Carrying Values and Estimated Fair Values Of Financial Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AppliedSciencesConsultingIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Applied Sciences Consulting Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AppliedSciencesConsultingIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Applied Sciences Consulting, Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AppliedSciencesConsultingIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Applied Sciences Consulting, Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationContingentConsiderationPostClosingAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Contingent Consideration Post Closing Adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationContingentConsiderationPostClosingAdjustments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination contingent consideration post closing adjustments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationContingentConsiderationPostClosingAdjustments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Post closing adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of ownership interest acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Voting Equity Interest Acquired, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeNamesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Trade Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeNamesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trade Names</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeNamesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trade Names [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Revenues by Business Lines</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from External Customers by Products and Services [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax assets, valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Valuation Allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. corporate tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Goodwill, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effective Income Tax Rate Reconciliation, Percent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective income tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Senior Notes due 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, to be Paid, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutPaymentPaidDays_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout Payment Paid Days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutPaymentPaidDays_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout payment paid days.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutPaymentPaidDays_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout payment paid days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeInterest_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_InvestmentIncomeInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Income, Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Geographical</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfMaturitiesOfOperatingAndFinanceLeaseLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Maturity Analysis of Future Undiscounted Cash Flows</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfMaturitiesOfOperatingAndFinanceLeaseLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Maturities Of Operating And Finance Lease Liabilities Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfMaturitiesOfOperatingAndFinanceLeaseLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of maturities of operating and finance lease liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentsForCappedCallOption_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payments for capped call option.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentsForCappedCallOption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments For Capped Call Option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentsForCappedCallOption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capped call transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Adjusted EBITDA Business Segment Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesRightOfUseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right of use assets, operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesRightOfUseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Operating Leases Right Of Use Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesRightOfUseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination recognized identifiable assets acquired and liabilities assumed operating leases right of use assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid in Capital, Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Issuance Costs, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt issuance costs incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Issuance Costs, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaidInEighteenMonthsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Paid in eighteen months [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaidInEighteenMonthsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Paid in eighteen months.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaidInEighteenMonthsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Paid in 18 months</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property Plant And Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AltamiraTechnologiesCorporationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Altamira Technologies Corporation [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AltamiraTechnologiesCorporationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Altamira Technologies Corporation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AltamiraTechnologiesCorporationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Altamira Technologies Corporation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ShareRepurchaseProgramAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_UnconsolidatedJointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unconsolidated Joint Ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_UnconsolidatedJointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unconsolidated Joint Ventures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_UnconsolidatedJointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unconsolidated joint ventures.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesShortTermLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Short-term lease liabilities, operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesShortTermLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Operating Leases Short Term Lease Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesShortTermLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination recognized identifiable assets acquired and liabilities assumed operating leases short-term lease liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MobilitySolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Mobility Solutions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MobilitySolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Mobility Solutions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MobilitySolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Mobility solutions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfFinancialStatementImpactFromChangesInEstimatesOnAnUnconsolidatedJointVentureTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Financial Statement Impact From Changes In Estimates on an Unconsolidated Joint Ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfFinancialStatementImpactFromChangesInEstimatesOnAnUnconsolidatedJointVentureTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of financial statement impact from changes in estimates on an unconsolidated joint venture.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfFinancialStatementImpactFromChangesInEstimatesOnAnUnconsolidatedJointVentureTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Financial Statement Impact From Changes In Estimates on an Unconsolidated Joint Venture [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disaggregation Of Revenue [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment, Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockCompensationPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockCompensationPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Equity-based Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockCompensationPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Disaggregation of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EquityMethodInvestmentLossAdjustmentAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Adjustment on unconsolidated joint venture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EquityMethodInvestmentLossAdjustmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment Loss Adjustment Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EquityMethodInvestmentLossAdjustmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Equity method investment loss adjustment amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign currency translation adjustment, net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevolvingCreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revolving Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevolvingCreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revolving Credit Facility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinitelivedIntangibleAssetsAcquired1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Carrying Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinitelivedIntangibleAssetsAcquired1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to reconcile net (loss) income to net cash used in operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsegments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsegments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ShareRepurchaseProgramDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalContributionsOfTreasuryStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments To Additional Paid In Capital Contributions Of Treasury Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalContributionsOfTreasuryStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to additional paid in capital contributions of treasury stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalContributionsOfTreasuryStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contributions Of Treasury Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounting Standards Update</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfAggregateAmountDebtRepayableTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Aggregate Amount of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfAggregateAmountDebtRepayableTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Aggregate Amount Debt Repayable Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfAggregateAmountDebtRepayableTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of aggregate amount debt repayable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BlacksignalTechnologiesLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Blacksignal Technologies, Llc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BlacksignalTechnologiesLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Blacksignal technologies, Llc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BlacksignalTechnologiesLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">BlackSignal Technologies, LLC.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DirectCostsOfContractsAndSellingGeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Direct Costs of Contracts and Selling, General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DirectCostsOfContractsAndSellingGeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Direct Costs Of Contracts And Selling General And Administrative Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DirectCostsOfContractsAndSellingGeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Direct costs of contracts and selling, general and administrative expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Description of Operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature of Operations [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Organization, Consolidation and Presentation of Financial Statements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Dilutive effect of convertible senior notes due 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Dilutive effect of convertible senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OrderOrProductionBacklogMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Backlog</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leases [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Contract with Customer, Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentPaymentTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, payment terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentPaymentTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Payment Terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee Lease Description [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Lease, Description [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amendment Flag</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="psn_ParsonsTransportationGroupIncAndAgainstAlstomSignalingOperationsLLCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Parsons Transportation Group, Inc. and against Alstom Signaling Operations LLC.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ParsonsTransportationGroupIncAndAgainstAlstomSignalingOperationsLLCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Parsons Transportation Group, Inc. And Against Alstom Signaling Operations L L C [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ParsonsTransportationGroupIncAndAgainstAlstomSignalingOperationsLLCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Parsons Transportation Group, Inc. and against Alstom Signaling Operations LLC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest on lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Interest Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities and Shareholders' Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description</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">Common Stock</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_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New Accounting Pronouncements Or Change In Accounting Principle [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update and Change in Accounting Principle [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Inventory, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TRSGroupIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">TRS group Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TRSGroupIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">TRS Group Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TRSGroupIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">TRS group, Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TRSGroupIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">TRS Group, Inc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accumulated depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireInterestInJointVenture_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Investments in unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireInterestInJointVenture_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Interest in Joint Venture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202403Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update 2024-03 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202403Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2024-03</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertiblePremiumPeriodPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument convertible premium period percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertiblePremiumPeriodPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Premium Period Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertiblePremiumPeriodPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Premium of reported sale price percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PortionAtFairValueFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Portion at Fair Value Measurement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PortionAtFairValueFairValueDisclosureMember_lbl" xlink:role="http://fasb.org/us-gaap/role/label/axisDefault">Portion at Fair Value Measurement [Member] [Default]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateImmaterialEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in accounting principle, accounting standards update, immaterial effect</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateImmaterialEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ProceedsFromPartialTerminationOfNoteHedgeAndWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from partial termination of note hedge and warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ProceedsFromPartialTerminationOfNoteHedgeAndWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Partial Termination of Note Hedge and Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ProceedsFromPartialTerminationOfNoteHedgeAndWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from partial termination of note hedge and warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractReceivableRetainageAssetsLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract retentions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractReceivableRetainageAssetsLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract Receivable Retainage Assets Liabilities Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractReceivableRetainageAssetsLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract receivable retainage assets (Liabilities) net.</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/terseLabel">Fair Value Hierarchy and NAV</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_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion percentage of stock price trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnings per share:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeStockOwnershipPlanESOPDisclosuresTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Employee Stock Ownership Plan E S O P Disclosures [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeStockOwnershipPlanESOPDisclosuresTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock Ownership Plan (ESOP) [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentForSettlementOfRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment for settlement of repurchases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentForSettlementOfRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment for Settlement of Repurchases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentForSettlementOfRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment for settlement of repurchases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit agreement maturity period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Expiration Period</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_CreditDerivativesContractTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Derivatives Contract Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right of use assets, operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right of use assets, operating leases (including $3,895 and $4,482 Right of use assets, operating leases of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Income Taxes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income attributable to noncontrolling interests</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalRedemptionOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redemption Of Warrants</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalRedemptionOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to additional paid in capital redemption of warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Type</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="psn_DecreaseInOperatingIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Decrease in operating income.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DecreaseInOperatingIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Decrease in operating income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DecreaseInOperatingIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease In Operating Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Central Index Key</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_AllowanceForDoubtfulAccountsReceivableCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Allowance for doubtful accounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNoteConvertedEachAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible note converted each amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNoteConvertedEachAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Note Converted Each Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNoteConvertedEachAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible note converted each amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TermLoanDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Term Loan Due Two Thousand Twenty Eight [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TermLoanDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Term loan due two thousand twenty eight.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TermLoanDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Term Loan Due 2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net increase (decrease) in cash, cash equivalents, and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive securities excluded from computation of earnings per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MarchTwoThousandAndTwentyFiveAuthorizationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">March Two Thousand and Twenty Five Authorization [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MarchTwoThousandAndTwentyFiveAuthorizationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">March two thousand and twenty five authorization.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MarchTwoThousandAndTwentyFiveAuthorizationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">March 2025 Authorization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total shares retired</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfAdoptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounting Standards Update</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ATCEnhancesParsonsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">ATC enhances Parsons [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNoteHedgeAndWarrantTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Note Hedge And Warrant Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNoteHedgeAndWarrantTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Note Hedge And Warrant Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNoteHedgeAndWarrantTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible note hedge and warrant transaction.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from issuance of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash proceeds from sales of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BaseRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Base Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BaseRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Base Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ParentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total Parsons Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ParentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DecreaseInEarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease in earnings per share diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DecreaseInEarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Decrease in earnings per share diluted.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LegalProceedingsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legal Proceedings [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LegalProceedingsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Legal Proceedings.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Estimate of Fair Value Measurement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToMinorityShareholders_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Distributions to noncontrolling interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToMinorityShareholders_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Noncontrolling Interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Intangible Assets Value on Purchase Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Intangible Asset, Acquired, Finite-Lived [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PartialUnwindOfTheExistingBondHedge_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">partial unwind of the existing bond hedge</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PartialUnwindOfTheExistingBondHedge_lbl" xlink:role="http://www.xbrl.org/2003/role/label">partial unwind of the existing bond hedge</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PartialUnwindOfTheExistingBondHedge_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Partial unwind of the existing bond hedge</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments in and advances to unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LongTermEmployeeIncentives_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term employee incentives</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LongTermEmployeeIncentives_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long Term Employee Incentives</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LongTermEmployeeIncentives_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Long-term employee incentives.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Quarterly Report</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReceivablesFromContractWithCustomerPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Receivables from contracts rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReceivablesFromContractWithCustomerPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Receivables from contract with customer percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReceivablesFromContractWithCustomerPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivables From Contract With Customer Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleNotesPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Convertible Notes Payable, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleNotesPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleNotesPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerRelationshipsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer Relationships</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, by Balance Sheet Grouping [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Threshold consecutive trading days</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TimeAndMaterialsContractMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Time-and-Materials</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseExistenceOfOptionToTerminate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease existence of option to terminate</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseExistenceOfOptionToTerminate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee lease existence of option to terminate.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Dilutive effect of stock-based awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Geographical</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage change in contract assets and liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract With Customer Asset Liability Cumulative Catchup Adjustment To Revenue Change In Measure Of Progress Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract with customer asset liability cumulative catchup adjustment to revenue change in measure of progress percent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognized included contract liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Revenue Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NorthRegionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US North Region [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Accrued Expenses And Other Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination recognized identifiable assets acquired and liabilities assumed current liabilities accrued expenses and other liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalBondHedgeTermination_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bond hedge termination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalBondHedgeTermination_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to additional paid in capital bond hedge termination.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalBondHedgeTermination_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments To Additional Paid In Capital Bond Hedge Termination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Stockholders' Equity Attributable to Noncontrolling Interest, Total</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MinorityInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive income, net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment, Nonconsolidated Investee [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite Lived Intangible Assets Acquired As Part Of Business Combination [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Intangible Asset, Acquired, Finite-Lived [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Prepaid Expense and Other Asset, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OtherSegmentItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Segment Items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OtherSegmentItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other segment items.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OtherSegmentItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other segment items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OtherSegmentItems_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other segment items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EMEAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EMEA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EMEAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Infrastructure - Europe, Middle East and Africa</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentToDeferredTaxAssetThroughRetainedEarnings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustment to deferred tax asset through retained earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentToDeferredTaxAssetThroughRetainedEarnings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment To Deferred Tax Asset Through Retained Earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentToDeferredTaxAssetThroughRetainedEarnings_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustment to deferred tax asset through retained earnings.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnRepurchaseOfDebtInstrument_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Repurchase of Debt Instrument</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnRepurchaseOfDebtInstrument_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible debt repurchase loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnRepurchaseOfDebtInstrument_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Convertible debt repurchase loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnRepurchaseOfDebtInstrument_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Convertible debt repurchase loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_UnusedTermLoanCommitmentsRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unused term loan commitments rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_UnusedTermLoanCommitmentsRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unused Term Loan Commitments Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_UnusedTermLoanCommitmentsRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unused term loan commitments rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Expense, Debt, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RatioOfSellingShareholdersMultiplier_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Ratio of selling shareholders multiplier.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RatioOfSellingShareholdersMultiplier_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ratio of Selling Shareholders Multiplier</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RatioOfSellingShareholdersMultiplier_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earn out payment due and payable to the selling shareholders, Multiplier</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets, Major Class Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock, Common, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury stock, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Impairment Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferred1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferred1_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total purchase price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Selling, General and Administrative Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling, general and administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling, General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustedEBITDAAttributableToNoncontrollingInterests_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Adjusted EBITDA attributable to noncontrolling interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustedEBITDAAttributableToNoncontrollingInterests_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjusted E B I T D A Attributable To Noncontrolling Interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustedEBITDAAttributableToNoncontrollingInterests_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjusted EBITDA attributable to noncontrolling interests.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Minimum</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_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Financial Information for Unconsolidated Joint Ventures</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleBusinessPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of business day period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleBusinessPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Business Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleBusinessPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument convertible business period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amortization expense of intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Intangible Assets</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</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerAssets1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change In Contract With Customer Assets1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerAssets1_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Change in contract with customer assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerAssets1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summay of Financial Assets and Liabilities Measured at Fair Value on a Recurrig Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDueTwoThousandTwentyNineMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible Senior Notes Due Two Thousand Twenty Nine.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDueTwoThousandTwentyNineMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Senior Notes Due Two Thousand Twenty Nine [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDueTwoThousandTwentyNineMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Senior Notes due 2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ProceedsFromPartialTerminationOfHedge_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Partial Termination of Hedge</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ProceedsFromPartialTerminationOfHedge_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from partial termination of hedge</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ProceedsFromPartialTerminationOfHedge_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from partial termination of hedge.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock repurchase value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased and Retired During Period, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubleaseIncome_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Sublease income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubleaseIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sublease Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net (including $323,655 and $337,270 Accounts receivable of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, after Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Accounts Receivable, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingencies (Note 12)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Leases [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DistributionsFromContributionsToEquityMethodInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net distributions from (contributions to) unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DistributionsFromContributionsToEquityMethodInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Distributions From Contributions To Equity Method Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DistributionsFromContributionsToEquityMethodInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Distributions from (contributions to) equity method investment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EurodollarMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Euro Currency Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EurodollarMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Eurodollar [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total present value of lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Margin interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Basis Spread on Variable Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableGrossCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accounts receivable, gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableGrossCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, before Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Changes in Carrying Value of Goodwill by Reporting Segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Goodwill [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Decrease in uncertain tax positions during the next twelve months</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease in Unrecognized Tax Benefits is Reasonably Possible</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNoncurrentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Issuance Costs, Noncurrent, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNoncurrentNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Long-term debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredFinanceCostsNoncurrentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Issuance Costs, Noncurrent, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Lease, Description [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee Lease Description [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finance leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Weighted Average Discount Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfChangesInRevenuesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of changes in revenues.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfChangesInRevenuesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Changes In Revenues [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfChangesInRevenuesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Changes in Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Income (Expense), Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest expense, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Income (Expense), Operating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net income including noncontrolling interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net income including noncontrolling interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term Debt, Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted Average Number of Shares Outstanding, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic weighted average number of shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAcquiredDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAcquiredDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAcquiredDuringPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Acquired During Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Expense Information Used by CODM, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Lived Tangible Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfMinimumLevelOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of minimum level of tax.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfMinimumLevelOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage of Minimum Level of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfMinimumLevelOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of minimum level of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_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_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Long-Term Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountPaidToAcquireVehiclesForContractorDefendantToPerformSecurityServices_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount paid to acquire vehicles for contractor defendant to perform security services.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountPaidToAcquireVehiclesForContractorDefendantToPerformSecurityServices_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount paid by relator to acquire vehicles for contractor defendant to perform security services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountPaidToAcquireVehiclesForContractorDefendantToPerformSecurityServices_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amount Paid To Acquire Vehicles For Contractor Defendant To Perform Security Services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">APIC, Share-Based Payment Arrangement, Increase for Cost Recognition, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Variable Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Stockholders' Equity Attributable to Parent, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Stockholders' Equity Attributable to Parent, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total joint venture equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Parsons Corporation shareholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Presentation and Principles of Consolidation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Accounting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_WeightedAverageRemainingLeaseTermAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Remaining Lease Term:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_WeightedAverageRemainingLeaseTermAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Remaining Lease Term [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_WeightedAverageRemainingLeaseTermAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average remaining lease term.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchaseAveragePricePaidPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Average price paid per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchaseAveragePricePaidPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchase Average Price Paid Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchaseAveragePricePaidPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock repurchase average price paid per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtLongtermAndShorttermCombinedAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt, Long-Term and Short-Term, Combined Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtLongtermAndShorttermCombinedAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DilutiveSecuritiesEffectOnBasicEarningsPerShareOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible senior notes if-converted method interest adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DilutiveSecuritiesEffectOnBasicEarningsPerShareOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Securities, Effect on Basic Earnings Per Share, Dilutive Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_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_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Use of Estimates, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToShareholdersEquityRelatingToReversalOfTaxBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments to Shareholders Equity Relating to Reversal of Tax Benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToShareholdersEquityRelatingToReversalOfTaxBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to shareholders equity relating to reversal of tax benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToShareholdersEquityRelatingToReversalOfTaxBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to shareholders equity relating to reversal of tax benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Equity Method Investments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock, Common [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Foreign Currency Transaction Gain (Loss), before Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Foreign currency transaction gains and losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss), Foreign Currency Transaction, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value of Financial Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TransactionRelatedCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Transaction-related costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TransactionRelatedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Related Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TransactionRelatedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction related costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContingentConsiderationMaximumPayoutAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum payout amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContingentConsiderationMaximumPayoutAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent consideration maximum payout amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContingentConsiderationMaximumPayoutAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contingent consideration maximum payout amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">United States</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/label">UNITED STATES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncontrollingInterestMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncontrollingInterestMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncontrolling Interest [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Equity in earnings of unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity in earnings (losses) of unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity in earnings (losses) of unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Equity in losses (earnings) of unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage change in contract liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract With Customer Liability Cumulative Catchup Adjustment To Revenue Change In Measure Of Progress Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract with customer liability cumulative catchup adjustment to revenue change in measure of progress percent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquired Finite Lived Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Asset, Acquired, Finite-Lived [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LeaseLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LeaseLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Liabilities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LeaseLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfChangesInContractAssetsAndContractLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Changes in Contract Assets and Contract Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfChangesInContractAssetsAndContractLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Changes In Contract Assets And Contract Liabilities Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfChangesInContractAssetsAndContractLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of changes in contract assets and contract liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyDamagesAwardedValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Award of damages in the total amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyDamagesAwardedValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss Contingency, Damages Awarded, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InProcessResearchAndDevelopmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">In Process Research and Development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InProcessResearchAndDevelopmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">In Process Research and Development [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plan Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Operating and Nonoperating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]</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_CreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Product and Service Sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cost of Goods and Services Sold, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Direct cost of contracts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Direct cost of contracts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsDisposalGroupIncludingDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of exchange rate changes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsDisposalGroupIncludingDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Treasury Stock, Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock repurchase value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Treasury stock, 38,708,253 shares at cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchaseProgramCommencementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock repurchase program commencement date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchaseProgramCommencementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchase Program Commencement Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchaseProgramCommencementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock repurchase program commencement date.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Gross Amount and Accumulated Amortization of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetsByMajorClassTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total shares repurchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased During Period, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock repurchased shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of reportable segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Reportable Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FinanceLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FinanceLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease Liability Payments Due After Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FinanceLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Finance lease liability payments due after year four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Debt instrument, outstanding amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Property, Plant and Equipment, Gross, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Property, Plant and Equipment, Gross, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property, Plant and Equipment, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseExistenceOfOptionToExtend_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease existence of option to extend</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseExistenceOfOptionToExtend_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Lease Existence Of Option To Extend</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseExistenceOfOptionToExtend_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee lease existence of option to extend.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income before income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Return of investments in unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Equity Method Investment, Distribution, Return of Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseOptionToExtend_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease option to extend</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseOptionToExtend_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Lease Option To Extend</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseOptionToExtend_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee lease option to extend.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities, Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DenominatorForBasicsAndDilutedEpsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Denominator for basic and diluted EPS.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DenominatorForBasicsAndDilutedEpsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Denominator For Basics And Diluted EPS [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DenominatorForBasicsAndDilutedEpsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Denominator for Basic and Diluted EPS:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DescriptionOfOperationsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description Of Operations Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DescriptionOfOperationsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of operations disclosure.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementBasisAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Basis [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</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_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise price of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Exercise Price of Warrants or Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SignificantSegmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Significant Segment Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SignificantSegmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Significant segment expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SignificantSegmentExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Selling, general and administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Remaining Unsatisfied Performance Obligations Expect to Satisfy</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Period End Date</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_EquityMethodInvestmentsAndJointVenturesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments and Joint Ventures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_WeightedAverageDiscountRateAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Discount Rate:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_WeightedAverageDiscountRateAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Discount Rate [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_WeightedAverageDiscountRateAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average discount rate.</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/terseLabel">Fair Value Hierarchy and NAV</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_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign currency translation gain (loss), net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gain (Loss) on Disposition of Property Plant Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Disposition of Property Plant Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Loss (gain) on disposal of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountRelatingToClaimsAssigned_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount relating to claims assigned.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountRelatingToClaimsAssigned_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amount Relating To Claims Assigned</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountRelatingToClaimsAssigned_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount relating to claims assigned</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout Liability [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EarnoutLiabilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted Average Amortization Period (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization Period (in years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingenciesByNatureOfContingencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss Contingency Nature [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReimbursableCostIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reimbursable cost incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReimbursableCostIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reimbursable Cost Incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReimbursableCostIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reimbursable cost incurred.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReconciliationFromNetIncomeToAdjustedEBITDAAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reconciliation From Net Income To Adjusted E B I T D A [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReconciliationFromNetIncomeToAdjustedEBITDAAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reconciliation from net income to adjusted EBITDA.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReconciliationFromNetIncomeToAdjustedEBITDAAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reconciliation: Segment Adjusted EBITDA to Net Income Attributable to Parsons Corporation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyNatureDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss Contingency, Nature [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Security, Excluded EPS Calculation [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractsReceivableClaimsAndUncertainAmounts_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Contracts Receivable, Claims and Uncertain Amounts, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractsReceivableClaimsAndUncertainAmounts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract assets, unapproved change orders, claims, and requests</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractsReceivableClaimsAndUncertainAmounts_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Contract assets, net claims recovery estimates</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfConvertibleSeniorNotesRepurchasedAtCash_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of convertible senior notes repurchased at cash.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationAndEmployeeBenefitPlansTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retirement Benefit Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationAndEmployeeBenefitPlansTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Compensation and Employee Benefit Plans [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilitiesPaymentsDueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finance Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilitiesPaymentsDueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease term of contract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Lease Term Of Contract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee lease term of contract.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares fully vested, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfFinanialStatementImpactFromRevisionsInEstimatesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary Of Finanial Statement Impact From Revisions In Estimates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfFinanialStatementImpactFromRevisionsInEstimatesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of finanial statement impact from revisions in estimates.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfFinanialStatementImpactFromRevisionsInEstimatesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Finanial Statement Impact From Revisions In Estimates [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterestAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Comprehensive income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterestAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseRightOfUseAssetAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseRightOfUseAssetAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Right-of-Use Asset, Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Variable Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Finite-Lived Intangible Assets, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Carrying Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Diluted weighted average number of shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity File Number</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="psn_ReversalOfTaxBenefitOfLossOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reversal of Tax Benefit of Loss On Extinguishment of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReversalOfTaxBenefitOfLossOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reversal of tax benefit of loss on extinguishment of debt.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReversalOfTaxBenefitOfLossOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reversal of tax benefit of loss on extinguishment of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses and other current assets (including $16,139 and $11,145 Prepaid expenses and other current assets of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Taxes Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income taxes payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Taxes Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Tax effect of unwind existing bond hedge</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202108Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2021-08</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202108Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update 2021-08 [Member]</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="psn_BusinessAcquisitionProFormaNetIncomeLossIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pro forma Net Income including noncontrolling interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessAcquisitionProFormaNetIncomeLossIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition Pro Forma Net Income Loss Including Portion Attributable To Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessAcquisitionProFormaNetIncomeLossIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business acquisition, pro forma net income (loss), including portion attributable to noncontrolling interest.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Acquired Finite Lived Intangible Asset By Major Class [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAcquiredFiniteLivedIntangibleAssetByMajorClassTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentsForTaxesPaidOnVestedStock_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Taxes paid on vested stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentsForTaxesPaidOnVestedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments For Taxes Paid On Vested Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentsForTaxesPaidOnVestedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payments for taxes paid on vested stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffectAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash, cash equivalents and restricted cash:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffectAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Excluding Exchange Rate Effect, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Finite-Lived Intangible Assets, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Finite-Lived Intangible Assets, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Carrying Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument, conversion price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Supplemental Balance Sheet and Other Information Related to Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Balance Sheet Information Related To Leases Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of balance sheet information related to leases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ESOP contribution expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOwnershipPlanESOPCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock Ownership Plan (ESOP), Compensation Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Loss on extinguishment of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gain (Loss) on Extinguishment of Debt, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Extinguishment of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss on extinguishment of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TargetAmountOfEarnoutRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Target amount of earnout revenue.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TargetAmountOfEarnoutRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Target Amount of Earnout Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TargetAmountOfEarnoutRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Target amount of earnout revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Useful life (years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueChangesInNetIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Value Changes In Net Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueChangesInNetIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued during period value changes in net income.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueChangesInNetIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in Net Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IssuanceOfEquitySecuritiesNetOfRetirement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of equity securities, net of retirement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IssuanceOfEquitySecuritiesNetOfRetirement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Equity Securities, Net Of Retirement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IssuanceOfEquitySecuritiesNetOfRetirement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of equity securities, net of retirement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New Accounting Pronouncements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentForEarnOutRevenueTarget_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment for earn out revenue target.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentForEarnOutRevenueTarget_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment For Earn Out Revenue Target</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PaymentForEarnOutRevenueTarget_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earn out revenue target, amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Contract liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Contract liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract liabilities (including $48,749 and $44,802 Contract liabilities of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares fully vested after credited service</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContributionsOfTreasuryStockToEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contributions of treasury stock to ESOP</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContributionsOfTreasuryStockToEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contributions of Treasury Stock to Employee Stock Ownership Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContributionsOfTreasuryStockToEmployeeStockOwnershipPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contributions of treasury stock to employee stock ownership plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInContractWithCustomerAsset_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInContractWithCustomerAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Contract with Customer, Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CarryingReportedAmountFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reported Value Measurement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CarryingReportedAmountFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Pension adjustments, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Pension adjustments, net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Shares, Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Shares, Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares, outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term lease liabilities, operating leases (including $2,004 and $2,395 Short-term lease liabilities, operating leases of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-term lease liabilities, operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Remaining unsatisfied performance obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdditionalDeferredTaxLiabilityRelatedToCapitalizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional deferred tax liability related to capitalized debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdditionalDeferredTaxLiabilityRelatedToCapitalizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Deferred Tax Liability Related To Capitalized Debt Issuance Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdditionalDeferredTaxLiabilityRelatedToCapitalizedDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional deferred tax liability related to Capitalized debt issuance cost.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Leases [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchases of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Repurchase of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncompeteAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Noncompete Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NoncompeteAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Noncompete Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Comprehensive income including noncontrolling interests, net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueStockHoldersEquityEliminations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Value Stock Holders Equity Eliminations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueStockHoldersEquityEliminations_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued during period value stock holders equity eliminations.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueStockHoldersEquityEliminations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SHE ELIMINATIONS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Businesses, Net of Cash Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Businesses, Net of Cash Acquired, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payments for acquisitions, net of cash acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FiniteLivedIntangibleAssetsAmortizableAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite Lived Intangible Assets Amortizable Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FiniteLivedIntangibleAssetsAmortizableAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Finite lived intangible assets amortizable amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FiniteLivedIntangibleAssetsAmortizableAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite Lived Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnings Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComputerEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Computer Systems and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComputerEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Computer Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net income attributable to Parsons Corporation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income attributable to Parsons Corporation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Accrued Expenses And Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in accrued expenses and other current liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertiblePrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertiblePrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Principal Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertiblePrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument convertible principal amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUncertainTaxPositionsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liability for income taxes associated with uncertain tax positions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUncertainTaxPositionsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liability for Uncertainty in Income Taxes, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Intangible Assets, Net (Excluding Goodwill), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets, Net (Excluding Goodwill)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating cash flows for operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConstructionInProgressMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Construction in Progress</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConstructionInProgressMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Construction in Progress [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid expenses and other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Terminated debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Repayments of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MinorityInterestIncreaseDecreaseFromContributionsToNoncontrollingInterestHolders_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minority interest increase (decrease) from contributions to noncontrolling interest holders.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MinorityInterestIncreaseDecreaseFromContributionsToNoncontrollingInterestHolders_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minority Interest Increase Decrease From Contributions To Noncontrolling Interest Holders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_MinorityInterestIncreaseDecreaseFromContributionsToNoncontrollingInterestHolders_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contributions By Noncontrolling Interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Year Focus</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_AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible debt inducement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SeriesASeniorNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Senior Note, Series A</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SeriesASeniorNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A Senior Note [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SeriesASeniorNoteMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series A senior note.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfPrincipalAmountToRedeemConvertibleSeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of principal amount to redeem convertible senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfPrincipalAmountToRedeemConvertibleSeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Principal Amount To Redeem Convertible Senior Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_PercentageOfPrincipalAmountToRedeemConvertibleSeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of principal amount to redeem convertible senior notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue, remaining performance obligation, expected timing of satisfaction, period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from investing activities:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationAndRetirementDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retirement Benefits [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable (including $21,234 and $58,914 Accounts payable of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate201912Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2019-12</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate201912Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update 2019-12 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update and Change in Accounting Principle [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Contract Assets and Contract Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NetCostOfPurchaseOfBondHedgesAndSaleOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase of bond hedges and sale of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NetCostOfPurchaseOfBondHedgesAndSaleOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cost Of Purchase Of Bond Hedges And Sale Of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NetCostOfPurchaseOfBondHedgesAndSaleOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net cost of purchase of bond hedges and sale of warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revolving Credit Facility Due Two Thousand Twenty Six [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revolving credit facility due two thousand twenty six.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revolving Credit Facility due 2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CostPlusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost-Plus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CostPlusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost Plus [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CostPlusMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cost plus.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Convertible Debt, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net carrying value of notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202006Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASC 2020-06</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202006Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update 2020-06 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NorthAmericaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">North America [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NorthAmericaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">North America</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effective Income Tax Rate Reconciliation, Tax Credit, Amount, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCredits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective tax rate and tax benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WriteOffOfDeferredDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acceleration charge of amortization of debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WriteOffOfDeferredDebtIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Debt Issuance Cost, Writeoff</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net assets acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total purchase price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract assets (including $38,585 and $41,318 Contract assets of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Contract with Customer, Asset, after Allowance for Credit Loss, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Asset, after Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionProFormaInformationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Supplemental Pro Forma Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionProFormaInformationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Pro Forma Information [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesIncomeTaxesPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Income taxes payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesIncomeTaxesPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination recognized identifiable assets acquired and liabilities assumed current liabilities income taxes payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesIncomeTaxesPayable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Income taxes payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractReceivableRetainageAssetLiabilitiesNetDueAfterOneYear_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract receivable retainage asset (liabilities) net, due after one year.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractReceivableRetainageAssetLiabilitiesNetDueAfterOneYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract retentions, not expected to be paid in next 12 months</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractReceivableRetainageAssetLiabilitiesNetDueAfterOneYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract Receivable Retainage Asset Liabilities Net Due After One Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Liability Assumed, Deferred Tax Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax liabiliities, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Deferred tax liabilities, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments in and Advances to Joint Ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments and Joint Ventures Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finance leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Weighted Average Remaining Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Segment Reporting Information By Segment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock repurchase program, remaining authorized repurchase amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program, Remaining Authorized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsegmentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsegments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsegmentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsegments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalEquityDeferredTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments To Additional Paid In Capital Equity Deferred Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalEquityDeferredTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to additional paid in capital equity deferred taxes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalEquityDeferredTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Deferred Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleMeasurementPeriodPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement period, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleMeasurementPeriodPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Measurement Period Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentConvertibleMeasurementPeriodPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument convertible measurement period percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IncreaseDecreaseInShareholdersEquityRelatingToReversalOfLossOnExtinguishmentOfDebtAndInducementExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease in Shareholders Equity Relating to Reversal of Loss on Extinguishment of Debt and Inducement Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IncreaseDecreaseInShareholdersEquityRelatingToReversalOfLossOnExtinguishmentOfDebtAndInducementExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase decrease in shareholders equity relating to reversal of loss on extinguishment of debt and inducement expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_IncreaseDecreaseInShareholdersEquityRelatingToReversalOfLossOnExtinguishmentOfDebtAndInducementExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in shareholders equity relating to reversal of loss on extinguishment of debt and inducement expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change In Contract With Customer Liability1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Change in contract with customer liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in contract liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConstructionEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Construction Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConstructionEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Construction Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConstructionEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Construction equipment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revolving Credit Facility Due Two Thousand Twenty Eight [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revolving credit facility due two thousand twenty eight.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandTwentyEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revolving Credit Facility due 2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</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_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in assets and liabilities, net of acquisitions and consolidated joint ventures:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LettersOfCreditOutstandingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Letters of credit outstanding amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LettersOfCreditOutstandingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Letters of Credit Outstanding, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfRevenuesAndPropertyAndEquipmentNetByGeographicAreaTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Revenues and Property and Equipment, Net by Geographic Area</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfRevenuesAndPropertyAndEquipmentNetByGeographicAreaTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Revenues And Property And Equipment Net By Geographic Area Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_SummaryOfRevenuesAndPropertyAndEquipmentNetByGeographicAreaTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of revenues and property and equipment, net by geographic area.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Rule 10b51 Arr Modified Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Rule 10b51 Arr Modified Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalizedContractCostImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalizedContractCostImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capitalized Contract Cost, Impairment Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StockRepurchaseProgramAuthorizedAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Authorized shares of common stock value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StockRepurchaseProgramAuthorizedAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program, Authorized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Senior Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Senior Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New Accounting Pronouncements Or Change In Accounting Principle [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements or Change in Accounting Principle [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdoptionDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in accounting principle, accounting standards update, adoption date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdoptionDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in Accounting Principle, Accounting Standards Update, Adoption Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trading Symbol(s)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Asset, Finite-Lived [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Related Party Transactions By Related Party [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchasePlanPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Repurchase Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchasePlanPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchase Plan Policy [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockRepurchasePlanPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock repurchase plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination, recognized identifiable assets acquired and liabilities assumed, deferred income taxes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Deferred income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from financing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Recurring</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Equity Method Investments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Equity Method Investments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetLiabilityNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net contract assets (liabilities)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetLiabilityNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract With Customer Asset Liability Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetLiabilityNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract with customer asset and liabilities net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total Parsons Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandThirtyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revolving Credit Facility due 2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandThirtyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revolving Credit Facility Due Two Thousand Thirty [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RevolvingCreditFacilityDueTwoThousandThirtyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revolving Credit Facility Due Two Thousand Thirty.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill And Intangible Assets Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromMinorityShareholders_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contributions by noncontrolling interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromMinorityShareholders_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Noncontrolling Interests</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed on Preliminary Purchase Price Allocation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DelayedDrawTermLoanDueTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Delayed Draw Term Loan Due Two Thousand Twenty Five [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DelayedDrawTermLoanDueTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Delayed draw term loan due two thousand twenty five.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DelayedDrawTermLoanDueTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Delayed Draw Term Loan Due 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueTaxesPaidOnVestedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Value Taxes Paid On Vested Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueTaxesPaidOnVestedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued during period value taxes paid on vested stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_StockIssuedDuringPeriodValueTaxesPaidOnVestedStock_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Taxes Paid On Vested Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BondHedgeTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bond hedge term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BondHedgeTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Bond Hedge Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BondHedgeTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Bond hedge term.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReversalOfDeferredTaxLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax liability reversed</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReversalOfDeferredTaxLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reversal of deferred tax liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerBasisOfPricingAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract with Customer, Basis of Pricing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerBasisOfPricingAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Basis of Pricing [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustedEBITDAAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjusted EBITDA attributable to Parsons Corporation</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustedEBITDAAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjusted EBITDA attributable to parent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustedEBITDAAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Adjusted EBITDA attributable to Parsons Corporation</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Depreciation and amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation and amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation, Depletion and Amortization, Nonproduction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BuildingAndBuildingImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Buildings and Leasehold Improvements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BuildingAndBuildingImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Building and Building Improvements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LegalProceedingsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legal Proceedings [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LegalProceedingsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Legal Proceedings.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Comprehensive Income [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Operating Lease Liability Payments Due After Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee operating lease liability payments due after year four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FederalSolutionSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Federal Solutions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FederalSolutionSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal Solution Segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FederalSolutionSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Federal Solution Segment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FederalSolutionSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Federal Solution Segment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment, Nonconsolidated Investee [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LossContingencyNumberOfClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of claims outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LossContingencyNumberOfClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss Contingency Number Of Claims</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LossContingencyNumberOfClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loss contingency, number of claims.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentIncreaseDecreaseForPeriodNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in term loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentIncreaseDecreaseForPeriodNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Increase (Decrease), Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentIncreaseDecreaseForPeriodNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Instrument, Increase (Decrease), Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Liabilities, Fair Value Disclosure, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities, fair value disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, $1 par value; authorized 1,000,000,000 shares; 145,677,597 and 145,676,335 shares issued; 56,923,103 and 56,103,965 public shares outstanding; 50,046,241 and 50,864,117 ESOP shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIncomeTaxesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income taxes receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIncomeTaxesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Income Taxes Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIncomeTaxesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination, recognized identifiable assets acquired and liabilities assumed, income taxes receivable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeasePrincipalPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financing cash flows from finance leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeasePrincipalPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Principal Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage change in contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract With Customer Asset Cumulative Catchup Adjustment To Revenue Change In Measure Of Progress Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ContractWithCustomerAssetCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contract with customer asset cumulative catchup adjustment to revenue change in measure of progress percent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityExpirationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Expiration Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityExpirationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit agreement termination date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OperatingLeaseNotYetCommencedExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease not yet commenced expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OperatingLeaseNotYetCommencedExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease Not Yet Commenced Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OperatingLeaseNotYetCommencedExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating lease not yet commenced expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total shareholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of debt issue costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amortization of debt fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerAssetsAndLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in contract assets and liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerAssetsAndLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change In Contract With Customer Assets And Liabilities Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerAssetsAndLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Change in contract with customer assets and liabilities net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChangeInContractWithCustomerAssetsAndLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Change in contract assets and liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Estimated Amortization Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MiddleEastMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Middle East</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MiddleEastMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Middle East [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountAttributableToContractualAndIndemnificationClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount attributable to contractual and indemnification claims</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountAttributableToContractualAndIndemnificationClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amount Attributable To Contractual And Indemnification Claims</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AmountAttributableToContractualAndIndemnificationClaims_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount attributable to contractual and indemnification claims</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentNumberOfSharesIssuableUponConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares issuable upon conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentNumberOfSharesIssuableUponConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Number Of Shares Issuable Upon Conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DebtInstrumentNumberOfSharesIssuableUponConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument number of shares issuable upon conversion.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdoptionOfAccountingStandardsUpdatePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adoption of Accounting Standards Update [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdoptionOfAccountingStandardsUpdatePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adoption of accounting standards update.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdoptionOfAccountingStandardsUpdatePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adoption of Accounting Standards Update 2024-04</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDue2025NoteHedgeAndWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible senior notes due 2025 note hedge and warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDue2025NoteHedgeAndWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Senior Notes Due 2025 Note Hedge And Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDue2025NoteHedgeAndWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Senior Notes Due 2025 Note Hedge And Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Comprehensive income attributable to noncontrolling interests, net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other current liabilities (including $191,847 and $195,747 Accrued expenses and other current liabilities of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Expenses And Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AccruedExpensesAndOtherCurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued expenses and other current liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets by Major Class</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Debt [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Term Loan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Term loan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Term Loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase of convertible senior notes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent Consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReversalOfLossOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reversal of Loss on Extinguishment of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReversalOfLossOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reversal of loss on extinguishment of debt.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReversalOfLossOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reversal of loss on extinguishment of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party Transaction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contracts with Customers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Business Acquisitions By Acquisition [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt and Credit Facilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CostOfConvertibleNoteHedgeTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of convertible note hedge transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CostOfConvertibleNoteHedgeTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost Of Convertible Note Hedge Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CostOfConvertibleNoteHedgeTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cost of convertible note hedge transactions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CostOfConvertibleNoteHedgeTransaction_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Capped call transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Nonoperating Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income (expense), net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LossContingencySoughtValueCivilPenaltyForEachAllegedViolationOfAct_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss contingency sought value, civil penalty for each alleged violation of Act</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LossContingencySoughtValueCivilPenaltyForEachAllegedViolationOfAct_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss Contingency Sought Value Civil Penalty For Each Alleged Violation Of Act</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LossContingencySoughtValueCivilPenaltyForEachAllegedViolationOfAct_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loss contingency sought value, civil penalty for each alleged violation of Act.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConsolidatedJointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Consolidated Joint Ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConsolidatedJointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Consolidated Joint Ventures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConsolidatedJointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Consolidated joint ventures.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SOFR Benchmark Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_GoodwillReportingOutOfBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill Reporting Out Of Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_GoodwillReportingOutOfBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Goodwill reporting out of balance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_GoodwillReportingOutOfBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill reporting out of balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetIncreaseDecreaseForContractAcquiredInBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquired contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetIncreaseDecreaseForContractAcquiredInBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Asset, Increase (Decrease) for Contract Acquired in Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Productive Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Capital expenditures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Productive Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased During Period, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock repurchase value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchases of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDueTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible Senior Notes Due Two Thousand Twenty Five.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDueTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Senior Notes Due Two Thousand Twenty Five [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleSeniorNotesDueTwoThousandTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Senior Notes Due 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReductionInQuarterlyCapValueOnStockRepurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reduction in quarterly cap value on stock repurchased.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReductionInQuarterlyCapValueOnStockRepurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reduction in Quarterly Cap Value on Stock Repurchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ReductionInQuarterlyCapValueOnStockRepurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reduction in quarterly cap value on stock repurchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Attributable to Parent, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted net income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted net income attributable to Parsons Corporation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Diluted net income attributable to Parsons Corporation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Other Comprehensive Income (Loss), Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated other comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForCommissions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commissions paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForCommissions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Commissions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_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_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Property Plant And Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseInterestPaymentOnLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating cash flows for finance leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseInterestPaymentOnLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Interest Payment on Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling, General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling, General and Administrative Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherOperatingIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Operating Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherOperatingIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CappedCallTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Capped call transaction.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CappedCallTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capped Call Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CappedCallTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capped Call Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityInitiationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit agreement date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityInitiationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Initiation Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_JointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Joint Ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_JointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Joint Ventures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_JointVenturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Joint ventures.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Diluted, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted earnings per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Diluted income (loss) per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Business Segment Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditDerivativesByContractTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Derivatives Contract Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CriticalInfrastructureSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Critical Infrastructure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CriticalInfrastructureSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Critical Infrastructure Segment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_CriticalInfrastructureSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Critical Infrastructure Segment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TwoThousandTwentyTwoDelayedDrawTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2022 Delayed Draw Term Loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TwoThousandTwentyTwoDelayedDrawTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Two Delayed Draw Term Loan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TwoThousandTwentyTwoDelayedDrawTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">2022 Delayed draw term loan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_TwoThousandTwentyTwoDelayedDrawTermLoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Delayed draw term loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DecreaseInNetIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease in net income net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_DecreaseInNetIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Decrease in net income net of tax.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Borrowed under credit agreement to partially fund the acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred, Liabilities Incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pro forma Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Pro Forma Information, Pro Forma Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityIncreaseDecreaseForContractAcquiredInBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquired contract liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityIncreaseDecreaseForContractAcquiredInBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Increase (Decrease) for Contract Acquired in Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite Lived Intangible Assets Amortization Expense After Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Finite lived intangible assets amortization expense after year four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFeeAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction fees and other third-party offering expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFeeAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Fee Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OperatingLeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Leases:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OperatingLeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Leases [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OperatingLeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating lease.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Lines of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Proceeds from Lines of Credit, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from borrowings under credit agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Debt amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Face Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revolving credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Maximum Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Acquisition [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateEarlyAdoption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in accounting principle, accounting standards update, early adoption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateEarlyAdoption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in Accounting Principle, Accounting Standards Update, Early Adoption [true false]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BccEngineeringLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">BCC Engineering, LLC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BccEngineeringLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">BCC Engineering, LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_BccEngineeringLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">BCC Engineering, LLC.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Intangibles</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Intangible Assets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherIntangibleAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Remaining Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FixedPriceContractMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fixed-Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FixedPriceContractMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fixed-Price Contract [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalEquityIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalEquityIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments To Additional Paid In Capital Equity Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalEquityIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to additional paid in capital equity income taxes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalEquityIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Equity Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentDividendsOrDistributions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Return on investments in unconsolidated joint ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentDividendsOrDistributions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Equity Method Investment, Distribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, net (including $2,462 and $2,488 Property and equipment of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use assets obtained in exchange for new finance lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-of-Use Asset Obtained in Exchange for Finance Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfConsolidatedBalanceSheetRelatedToUnconsolidatedJointVenturesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Consolidated Balance Sheet Related to Services Provided to Unconsolidated Joint Ventures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfConsolidatedBalanceSheetRelatedToUnconsolidatedJointVenturesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Consolidated Balance Sheet Related To Unconsolidated Joint Ventures Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ScheduleOfConsolidatedBalanceSheetRelatedToUnconsolidatedJointVenturesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of consolidated balance sheet related to unconsolidated joint ventures.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_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_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">End of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodEndLabel">End</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Operating income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillForeignCurrencyTranslationGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign Exchange</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillForeignCurrencyTranslationGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Foreign Currency Translation, Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retained Earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContingentConsiderationTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Assets, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NumberOfCommonStockAcquiredByOffsettingSaleWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of common stock acquired by offsetting sale warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NumberOfCommonStockAcquiredByOffsettingSaleWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Common Stock Acquired By Offsetting Sale Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NumberOfCommonStockAcquiredByOffsettingSaleWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of common stock acquired by offsetting sale warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToWarrantRepurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to warrant repurchased.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToWarrantRepurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments To Warrant Repurchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToWarrantRepurchased_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repurchase of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-Based Payment Arrangement, Noncash Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChesapeakeTechnologyInternationalCorpMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Chesapeake Technology International, Corp [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChesapeakeTechnologyInternationalCorpMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Chesapeake Technology International, Corp [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ChesapeakeTechnologyInternationalCorpMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Chesapeake Technology International, Corp</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNotesConvertedEachIntoSharesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible notes converted each into shares of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNotesConvertedEachIntoSharesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes Converted Each Into Shares Of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNotesConvertedEachIntoSharesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible notes converted each into shares of common stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FinanceLeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finance Leases:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FinanceLeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Leases [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FinanceLeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Finance leases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Liabilities, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Noncurrent liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OtherIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other income (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OtherIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Income Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_OtherIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other income (expense).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Discount Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term lease liabilities, operating leases (including $1,888 and $2,083 Long-term lease liabilities, operating leases of consolidated joint ventures)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-term lease liabilities, operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Long-term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash (used in) provided by financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdditionalPaymentForSellingShareholders_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional payment for selling shareholders.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdditionalPaymentForSellingShareholders_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Payment For Selling Shareholders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdditionalPaymentForSellingShareholders_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional amount agreed to pay the selling shareholders in the event an earn out EBITDA target is exceeded</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Lease Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in accounting principle, accounting standards update, adopted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in Accounting Principle, Accounting Standards Update, Adopted [true false]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Developed Technologies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Developed Technology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Developed Technology Rights [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Liabilities, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnings per share:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share Reconciliation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Goodwill [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Recognized Asset Acquired, Receivable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USGovernmentCorporationsAndAgenciesSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US Government Corporations and Agencies Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USGovernmentCorporationsAndAgenciesSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. Federal Government and Agencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonUsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rest of World</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonUsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-US [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LineOfCreditFacilityNumberOfExtensions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit agreement number of extensions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LineOfCreditFacilityNumberOfExtensions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line Of Credit Facility Number Of Extensions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_LineOfCreditFacilityNumberOfExtensions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Line of credit facility number of extensions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalRepurchasesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repurchases of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalRepurchasesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments To Additional Paid In Capital Repurchases Of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalRepurchasesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments to additional paid in capital repurchases of common stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_AdjustmentsToAdditionalPaidInCapitalRepurchasesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchases of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Contract with Customer, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosureItemAmountsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Furniture and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Furniture and Fixtures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repayments of borrowings under credit agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Repayments of Lines of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repayments of borrowings under credit agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New Accounting Pronouncements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update and Change in Accounting Principle [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnbilledReceivablesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unbilled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnbilledReceivablesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unbilled Receivables, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Contract with Customer, Asset, after Allowance for Credit Loss, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerAssetNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Asset, after Allowance for Credit Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other long-term liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfTreasuryStockByClassTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Repurchase Program</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfTreasuryStockByClassTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Treasury Stock [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNotesConvertedSalePriceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible notes converted sale price of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNotesConvertedSalePriceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes Converted Sale Price Of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_ConvertibleNotesConvertedSalePriceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Notes Converted Sale Price Of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revolving credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Current Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shareholders' equity:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term Debt, Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, maturity period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RepurchasesOfConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchases of convertible notes due 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RepurchasesOfConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Repurchases of convertible notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RepurchasesOfConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Repurchases of Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_RepurchasesOfConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repurchases of convertible notes due 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Presentation and Principles of Consolidation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Local Phone Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Local Phone Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NonRule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non Rule 10b51 Arr Modified Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NonRule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non Rule 10b51 Arr Modified Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EmployeeStockOwnershipPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ESOP</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EmployeeStockOwnershipPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock Ownership Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_EmployeeStockOwnershipPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Employee Stock Ownership Plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance Lease, Liability, to be Paid, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NumeratorForBasicsAndDilutedEpsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Numerator for basics and diluted EPS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NumeratorForBasicsAndDilutedEpsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Numerator For Basics And Diluted EPS [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_NumeratorForBasicsAndDilutedEpsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Numerator for Basic and Diluted EPS:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Policies [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="psn_FinanceLeasesOtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other noncurrent assets</link:label>
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  <xsd:element id="psn_SummaryOfChangesInRevenuesTableTextBlock" name="SummaryOfChangesInRevenuesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_MinorityInterestIncreaseDecreaseFromContributionsToNoncontrollingInterestHolders" name="MinorityInterestIncreaseDecreaseFromContributionsToNoncontrollingInterestHolders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_WeightedAverageRemainingLeaseTermAbstract" name="WeightedAverageRemainingLeaseTermAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_LesseeLeaseTermOfContract" name="LesseeLeaseTermOfContract" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_PaymentForEarnOutRevenueTarget" name="PaymentForEarnOutRevenueTarget" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ContractWithCustomerAssetCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" name="ContractWithCustomerAssetCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_AdjustmentsToShareholdersEquityRelatingToReversalOfTaxBenefit" name="AdjustmentsToShareholdersEquityRelatingToReversalOfTaxBenefit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_CostPlusMember" name="CostPlusMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_TermLoanMember" name="TermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_TRSGroupIncMember" name="TRSGroupIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_SummaryOfFinancialStatementImpactFromChangesInEstimatesOnAnUnconsolidatedJointVentureTableTextBlock" name="SummaryOfFinancialStatementImpactFromChangesInEstimatesOnAnUnconsolidatedJointVentureTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesIncomeTaxesPayable" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesIncomeTaxesPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ContractWithCustomerLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" name="ContractWithCustomerLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_PercentageOfMinimumLevelOfTax" name="PercentageOfMinimumLevelOfTax" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_PercentageOfConvertibleSeniorNotesRepurchasedAtCash" name="PercentageOfConvertibleSeniorNotesRepurchasedAtCash" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="psn_ChesapeakeTechnologyInternationalCorpMember" name="ChesapeakeTechnologyInternationalCorpMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ConvertibleSeniorNotesDueTwoThousandTwentyFiveMember" name="ConvertibleSeniorNotesDueTwoThousandTwentyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_OperatingLeasesAbstract" name="OperatingLeasesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ContingentConsiderationMaximumPayoutAmount" name="ContingentConsiderationMaximumPayoutAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_AdditionalPaymentForSellingShareholders" name="AdditionalPaymentForSellingShareholders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_BusinessAcquisitionProFormaNetIncomeLossIncludingPortionAttributableToNoncontrollingInterest" name="BusinessAcquisitionProFormaNetIncomeLossIncludingPortionAttributableToNoncontrollingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_AdjustmentsToAdditionalPaidInCapitalEquityDeferredTaxes" name="AdjustmentsToAdditionalPaidInCapitalEquityDeferredTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_BondHedgeTerm" name="BondHedgeTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ConvertibleNoteConvertedEachAmount" name="ConvertibleNoteConvertedEachAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_DefenseAndIntelligenceMember" name="DefenseAndIntelligenceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_CommonStockSharesOutstandingIncludingEmployeeStockOwnershipPlanShares" name="CommonStockSharesOutstandingIncludingEmployeeStockOwnershipPlanShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="psn_SignificantSegmentExpense" name="SignificantSegmentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LossContingencyNumberOfClaims" name="LossContingencyNumberOfClaims" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_DebtInstrumentConvertibleBusinessPeriod" name="DebtInstrumentConvertibleBusinessPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_AmountPaidToAcquireVehiclesForContractorDefendantToPerformSecurityServices" name="AmountPaidToAcquireVehiclesForContractorDefendantToPerformSecurityServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DebtInstrumentConvertibleMeasurementPeriodPercentage" name="DebtInstrumentConvertibleMeasurementPeriodPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ConsolidatedJointVenturesMember" name="ConsolidatedJointVenturesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock" name="ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_SeriesASeniorNoteMember" name="SeriesASeniorNoteMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ContractWithCustomerAssetLiabilityNet" name="ContractWithCustomerAssetLiabilityNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DistributionsFromContributionsToEquityMethodInvestment" name="DistributionsFromContributionsToEquityMethodInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_FiniteLivedIntangibleAssetsAmortizableAmount" name="FiniteLivedIntangibleAssetsAmortizableAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_SummaryOfFinanialStatementImpactFromRevisionsInEstimatesTableTextBlock" name="SummaryOfFinanialStatementImpactFromRevisionsInEstimatesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_NumeratorForBasicsAndDilutedEpsAbstract" name="NumeratorForBasicsAndDilutedEpsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ContractWithCustomerAdjustmentToRevenueImpactOfChangesInEstimatedClaimsOrIncentivesOverThreshold" name="ContractWithCustomerAdjustmentToRevenueImpactOfChangesInEstimatedClaimsOrIncentivesOverThreshold" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_AdjustmentsToAdditionalPaidInCapitalRedemptionOfWarrants" name="AdjustmentsToAdditionalPaidInCapitalRedemptionOfWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_AmountRelatingToClaimsAssigned" name="AmountRelatingToClaimsAssigned" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_ReversalOfDeferredTaxLiability" name="ReversalOfDeferredTaxLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DebtInstrumentNumberOfSharesIssuableUponConversion" name="DebtInstrumentNumberOfSharesIssuableUponConversion" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ProceedsFromPartialTerminationOfHedge" name="ProceedsFromPartialTerminationOfHedge" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_BlacksignalTechnologiesLlcMember" name="BlacksignalTechnologiesLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_JointVenturesMember" name="JointVenturesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AdditionalDeferredTaxLiabilityRelatedToCapitalizedDebtIssuanceCost" name="AdditionalDeferredTaxLiabilityRelatedToCapitalizedDebtIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_GoodwillReportingOutOfBalance" name="GoodwillReportingOutOfBalance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_StockIssuedDuringPeriodValueChangesInNetIncome" name="StockIssuedDuringPeriodValueChangesInNetIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_AccountingStandardsUpdate2024-04Member" name="AccountingStandardsUpdate2024-04Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_FinanceLeasesOtherAssetsNoncurrent" name="FinanceLeasesOtherAssetsNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities" name="IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_MarchTwoThousandAndTwentyFiveAuthorizationMember" name="MarchTwoThousandAndTwentyFiveAuthorizationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" name="FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DebtInstrumentExerciseOfOptionByInitialPurchasersAggregatePrincipalAmount" name="DebtInstrumentExerciseOfOptionByInitialPurchasersAggregatePrincipalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_AccruedExpensesAndOtherCurrentLiabilities" name="AccruedExpensesAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ChangeInContractWithCustomerLiability1" name="ChangeInContractWithCustomerLiability1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_LesseeLeaseOptionToTerminate" name="LesseeLeaseOptionToTerminate" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_EmployeeStockOwnershipPlanMember" name="EmployeeStockOwnershipPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_IncreaseDecreaseInShareholdersEquityRelatingToReversalOfLossOnExtinguishmentOfDebtAndInducementExpenses" name="IncreaseDecreaseInShareholdersEquityRelatingToReversalOfLossOnExtinguishmentOfDebtAndInducementExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_Rule10B51ArrModifiedFlag" name="Rule10B51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_AdjustedEBITDAAttributableToNoncontrollingInterests" name="AdjustedEBITDAAttributableToNoncontrollingInterests" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LossContingencySoughtValueCivilPenaltyForEachAllegedViolationOfAct" name="LossContingencySoughtValueCivilPenaltyForEachAllegedViolationOfAct" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_NonRule10B51ArrModifiedFlag" name="NonRule10B51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_CappedCallTransactionMember" name="CappedCallTransactionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_CriticalInfrastructureSegmentMember" name="CriticalInfrastructureSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_PercentageOfPrincipalAmountToRedeemConvertibleSeniorNotes" name="PercentageOfPrincipalAmountToRedeemConvertibleSeniorNotes" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="psn_OperatingLeaseNotYetCommencedExpense" name="OperatingLeaseNotYetCommencedExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_OtherSegmentItems" name="OtherSegmentItems" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" name="LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_BusinessCombinationContingentConsiderationPostClosingAdjustments" name="BusinessCombinationContingentConsiderationPostClosingAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_EarnoutPayment" name="EarnoutPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_EquityBasedCompensationIncomeExpense" name="EquityBasedCompensationIncomeExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_TransactionRelatedCosts" name="TransactionRelatedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_BccEngineeringLlcMember" name="BccEngineeringLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ConvertibleNotesConvertedSalePriceOfCommonStock" name="ConvertibleNotesConvertedSalePriceOfCommonStock" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="psn_NetCostOfPurchaseOfBondHedgesAndSaleOfWarrants" name="NetCostOfPurchaseOfBondHedgesAndSaleOfWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_ChangeInContractWithCustomerAssets1" name="ChangeInContractWithCustomerAssets1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DecreaseInEarningsPerShareDiluted" name="DecreaseInEarningsPerShareDiluted" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_StockRepurchaseProgramCommencementDate" name="StockRepurchaseProgramCommencementDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ContributionsOfTreasuryStockToEmployeeStockOwnershipPlan" name="ContributionsOfTreasuryStockToEmployeeStockOwnershipPlan" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DebtInstrumentConvertiblePremiumPeriodPercentage" name="DebtInstrumentConvertiblePremiumPeriodPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_LegalProceedingsTable" name="LegalProceedingsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_PaidInEighteenMonthsMember" name="PaidInEighteenMonthsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_OtherIncomeExpense" name="OtherIncomeExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_DecreaseInOperatingIncome" name="DecreaseInOperatingIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_OtherReconciliationFromNetIncomeToAdjustedEBITDA" name="OtherReconciliationFromNetIncomeToAdjustedEBITDA" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_AdjustmentsToWarrantRepurchased" name="AdjustmentsToWarrantRepurchased" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_ConvertibleSeniorNotesDue2025NoteHedgeAndWarrantsMember" name="ConvertibleSeniorNotesDue2025NoteHedgeAndWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_StockRepurchasePlanPolicyTextBlock" name="StockRepurchasePlanPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_LineOfCreditFacilityNumberOfExtensions" name="LineOfCreditFacilityNumberOfExtensions" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_FederalSolutionSegmentMember" name="FederalSolutionSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_PaymentForSettlementOfRepurchases" name="PaymentForSettlementOfRepurchases" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_DebtInstrumentConvertiblePrincipalAmount" name="DebtInstrumentConvertiblePrincipalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ReimbursableCostIncurred" name="ReimbursableCostIncurred" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_AccumulatedOtherComprehensiveIncomeEquityLiabilities" name="AccumulatedOtherComprehensiveIncomeEquityLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ConnectedCommunitiesMember" name="ConnectedCommunitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_DelayedDrawTermLoanDueTwoThousandTwentyFiveMember" name="DelayedDrawTermLoanDueTwoThousandTwentyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_RevolvingCreditFacilityDueTwoThousandThirtyMember" name="RevolvingCreditFacilityDueTwoThousandThirtyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_TwoThousandTwentyTwoDelayedDrawTermLoanMember" name="TwoThousandTwentyTwoDelayedDrawTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_DenominatorForBasicsAndDilutedEpsAbstract" name="DenominatorForBasicsAndDilutedEpsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AdjustmentsToAdditionalPaidInCapitalContributionsOfTreasuryStock" name="AdjustmentsToAdditionalPaidInCapitalContributionsOfTreasuryStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_AccumulatedOtherComprehensiveIncomeEquityAccountsReceivable" name="AccumulatedOtherComprehensiveIncomeEquityAccountsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DirectCostsOfContractsAndSellingGeneralAndAdministrativeExpenseMember" name="DirectCostsOfContractsAndSellingGeneralAndAdministrativeExpenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_EngineeredSystemsMember" name="EngineeredSystemsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_IssuanceOfEquitySecuritiesNetOfRetirement" name="IssuanceOfEquitySecuritiesNetOfRetirement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_AltamiraTechnologiesCorporationMember" name="AltamiraTechnologiesCorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredIncomeTaxes" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredIncomeTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_FinanceLeaseLiabilityPaymentsDueAfterYearFour" name="FinanceLeaseLiabilityPaymentsDueAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ScheduleOfMaturitiesOfOperatingAndFinanceLeaseLiabilitiesTableTextBlock" name="ScheduleOfMaturitiesOfOperatingAndFinanceLeaseLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ContractReceivableRetainageAssetsLiabilitiesNet" name="ContractReceivableRetainageAssetsLiabilitiesNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_ReversalOfLossOnExtinguishmentOfDebt" name="ReversalOfLossOnExtinguishmentOfDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_UnconsolidatedJointVenturesMember" name="UnconsolidatedJointVenturesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ConstructionEquipmentMember" name="ConstructionEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AdjustmentToDeferredTaxAssetThroughRetainedEarnings" name="AdjustmentToDeferredTaxAssetThroughRetainedEarnings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_AmountPaidPerMonthToContractorDefendantByRelatorOnFalseClaims" name="AmountPaidPerMonthToContractorDefendantByRelatorOnFalseClaims" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DelayedDrawTermLoanDueTwoThousandTwentyEightMember" name="DelayedDrawTermLoanDueTwoThousandTwentyEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_PercentageOfBondHedgeAndWarrantTransactionsIncreasedConversionPrice" name="PercentageOfBondHedgeAndWarrantTransactionsIncreasedConversionPrice" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_CostOfConvertibleNoteHedgeTransaction" name="CostOfConvertibleNoteHedgeTransaction" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_RepurchasesOfConvertibleNotes" name="RepurchasesOfConvertibleNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_BilledReceivablesCurrent" name="BilledReceivablesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LesseeLeaseExistenceOfOptionToTerminate" name="LesseeLeaseExistenceOfOptionToTerminate" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_PaymentsForCappedCallOption" name="PaymentsForCappedCallOption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_DecreaseInNetIncomeNetOfTax" name="DecreaseInNetIncomeNetOfTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LegalProceedingsLineItems" name="LegalProceedingsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_LesseeLeaseOptionToExtend" name="LesseeLeaseOptionToExtend" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_DescriptionOfOperationsDisclosureAbstract" name="DescriptionOfOperationsDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AmountAttributableToContractualAndIndemnificationClaims" name="AmountAttributableToContractualAndIndemnificationClaims" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_EquityMethodInvestmentLossAdjustmentAmount" name="EquityMethodInvestmentLossAdjustmentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_StockRepurchaseAveragePricePaidPerShare" name="StockRepurchaseAveragePricePaidPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_PartialUnwindOfTheExistingBondHedge" name="PartialUnwindOfTheExistingBondHedge" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_AppliedSciencesConsultingIncMember" name="AppliedSciencesConsultingIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ScheduleOfConsolidatedBalanceSheetRelatedToUnconsolidatedJointVenturesTableTextBlock" name="ScheduleOfConsolidatedBalanceSheetRelatedToUnconsolidatedJointVenturesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
