PRTA


Line plots across dimensions of each concept
Line plots across concepts
Tables

Table of contents



us-gaap:CommonStockValue
us-gaap:StatementEquityComponents
us-gaap:SharesOutstanding

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesAuthorized

us-gaap:CommonStockSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareBasicAndDiluted

us-gaap:GeneralAndAdministrativeExpense

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxesPaidNet

us-gaap:InterestIncomeExpenseNet

us-gaap:NetIncomeLoss
us-gaap:StatementEquityComponents

us-gaap:NonoperatingIncomeExpense

us-gaap:OperatingExpenses

us-gaap:OperatingIncomeLoss

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:ResearchAndDevelopmentExpense

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ProductOrService

us-gaap:Revenues

us-gaap:Assets

us-gaap:Liabilities

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity

us-gaap:AssetsCurrent

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:AccountsReceivableNetCurrent
us-gaap:CounterpartyName, us-gaap:TypeOfArrangement

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:MachineryAndEquipmentGross

us-gaap:AssetsNoncurrent

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:LeaseholdImprovementsGross

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:PropertyPlantAndEquipmentNet
us-gaap:StatementGeographical

us-gaap:DeferredTaxAssetsLiabilitiesNet

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OtherAssetsNoncurrent

us-gaap:AccountsPayableCurrent

us-gaap:AccruedIncomeTaxesCurrent

us-gaap:LiabilitiesCurrent

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OtherLiabilitiesCurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:OperatingLeaseLiability

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue
us-gaap:StatementGeographical

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquity

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapital

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:StockIssuedDuringPeriodValueNewIssues
us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents, us-gaap:SubsidiarySaleOfStock
us-gaap:SubsidiarySaleOfStock

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:DepreciationDepletionAndAmortization

us-gaap:IncreaseDecreaseInAccountsReceivable

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:StatementEquityComponents

us-gaap:ShareBasedCompensation
us-gaap:IncomeStatementLocation

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
us-gaap:PlanName

us-gaap:DeferredTaxAssetsNet

us-gaap:UnrecognizedTaxBenefits

us-gaap:DeferredTaxAssetsValuationAllowance

prta:Amortizationofrightofuseasset
us-gaap:CounterpartyName, us-gaap:ProductOrService, us-gaap:SubsequentEventType
prta:CollaborationAgreementExerciseFeeUSRightsPerProgram
us-gaap:CounterpartyName, us-gaap:ProductOrService, us-gaap:SubsequentEventType
prta:CollaborationAgreementPotentialRegulatoryandCommercialMilestonePaymentsPerProgram

prta:CollaborationRevenue

prta:DeferredTaxAssetsPeriodIncreaseDecrease

prta:DeferredTaxAssetsPeriodIncreaseDecreaseTaxCutsAndJobsAct

prta:IncreaseDecreaseinOperatingLeaseLiability
us-gaap:CounterpartyName, us-gaap:TypeOfArrangement
prta:LicenseAgreementPotentialAlternativeCommercialSalesMilestones
us-gaap:CounterpartyName, us-gaap:TypeOfArrangement
prta:LicenseAgreementPotentialPaymentUponAchievementofDevelopmentRegulatoryandVariousFirstCommercialSalesMilestones
us-gaap:CounterpartyName, us-gaap:TypeOfArrangement
prta:LicenseAgreementPotentialPaymentforAchievementofnonU.S.CommercialSalesMilestones
us-gaap:CounterpartyName, us-gaap:TypeOfArrangement
prta:LicensingAgreementCostAllocationPercentage
us-gaap:CounterpartyName, us-gaap:TypeOfArrangement
prta:LicensingAgreementPortionofRevenueandExpensesAttributabletoCompanyPercentage
us-gaap:TypeOfArrangement
us-gaap:CounterpartyName, us-gaap:SubsequentEventType
prta:MilestoneAchievementClinicalMilestone

prta:OfferingCostsIncludedInAccountsPayableAndAccruedLiabilities
us-gaap:IncomeTaxAuthorityName
prta:PotentialWithholdingTaxRate

prta:ReceivableFromOptionsExercises
us-gaap:CounterpartyName, us-gaap:TypeOfArrangement
prta:ResearchAndDevelopmentPaymentToCollaborationPartnerRecordedAsResearchAndDevelopmentExpense

prta:SharebasedCompensationNetTaxShortfallExcessTaxBenefitAmountBookedtoIncomeTaxProvision

prta:SharebasedCompensationnonrestructuring
us-gaap:SubsidiarySaleOfStock
prta:StockIssuanceCosts

us-gaap:AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition
us-gaap:StatementEquityComponents

us-gaap:AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts
us-gaap:StatementEquityComponents, us-gaap:SubsidiarySaleOfStock

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect

us-gaap:DeferredIncomeTaxesAndTaxCredits

us-gaap:Depreciation
us-gaap:IncomeTaxAuthorityName
us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities

us-gaap:IncreaseDecreaseInOtherOperatingAssets

us-gaap:IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

us-gaap:NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1

us-gaap:OperatingLeaseCost

us-gaap:OperatingLeasePayments

us-gaap:PaymentsOfStockIssuanceCosts
dei:LegalEntity, us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType
us-gaap:PaymentsToAcquireBusinessesGross

us-gaap:PaymentsToAcquireMachineryAndEquipment

us-gaap:ProceedsFromIssuanceOfCommonStock

us-gaap:ProceedsFromStockOptionsExercised

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesNewIssues
us-gaap:StatementEquityComponents, us-gaap:SubsidiarySaleOfStock
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised

us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised
us-gaap:StatementEquityComponents

dei:EntityCommonStockSharesOutstanding
us-gaap:CounterpartyName, us-gaap:ProductOrService
prta:ASC605AllocatedConsiderationToDeliverables

prta:AccruedResearchAndDevelopmentCurrent

prta:DeferredSharesSharesAuthorized

prta:DeferredTaxAssetPeriodIncreaseDecreaseAmericanRescuePlanAct

prta:DeferredTaxAssetsLeaseLiabilities

prta:DeferredTaxLiabilitiesOperatingLeaseRightofUseAssets

prta:LesseeOperatingLeaseLiabilityNominalPayments
us-gaap:CounterpartyName, us-gaap:SubsequentEventType
prta:NearTermClinicalMilestone

prta:NumberOfOrdinarySharesTenderedForExchangeUnderTheOptionExchage

prta:PurchaseandContractualObligationDueAfterFifthYear

prta:PurchaseandContractualObligationDueNextFiscalYear

prta:PurchaseandContractualObligationDueinFourthYear

prta:PurchaseandContractualObligationDueinSecondYear

prta:PurchaseandContractualObligationDueinThirdYear

prta:PurchaseandContractualObligationRemainderofFiscalYear

prta:PurchaseandContractualObligationTotal

prta:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueRelatedToVestedOptions

us-gaap:AccruedProfessionalFeesCurrent
dei:LegalEntity, us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType
us-gaap:BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh

us-gaap:CapitalizedComputerSoftwareGross

us-gaap:ContractualObligation
us-gaap:BalanceSheetLocation
us-gaap:OtherCommitments
us-gaap:OtherCommitments
us-gaap:ContractualObligationDueAfterFifthYear
us-gaap:OtherCommitments
us-gaap:ContractualObligationDueInFifthYear
us-gaap:OtherCommitments
us-gaap:ContractualObligationDueInFourthYear
us-gaap:OtherCommitments
us-gaap:ContractualObligationDueInNextTwelveMonths
us-gaap:OtherCommitments
us-gaap:ContractualObligationDueInSecondYear
us-gaap:OtherCommitments
us-gaap:ContractualObligationDueInThirdYear
us-gaap:OtherCommitments
us-gaap:ContractualObligationFutureMinimumPaymentsDueRemainderOfFiscalYear

us-gaap:DeferredIncomeTaxAssetsNet

us-gaap:DeferredRevenueCurrent

us-gaap:DeferredRevenueNoncurrent

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsTaxCreditCarryforwardsResearch
us-gaap:IncomeTaxAuthority

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:EmployeeRelatedLiabilitiesCurrent

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear

us-gaap:LessorOperatingLeasePaymentsToBeReceived

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFourYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths

us-gaap:LessorOperatingLeasePaymentsToBeReceivedRemainderOfFiscalYear

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThreeYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedTwoYears
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:MoneyMarketFundsAtCarryingValue
prta:TypeofLossCarryovers, us-gaap:IncomeTaxAuthority
us-gaap:OperatingLossCarryforwards
us-gaap:IncomeTaxAuthority

us-gaap:OtherSundryLiabilitiesCurrent
us-gaap:BalanceSheetLocation
us-gaap:PurchaseCommitmentRemainingMinimumAmountCommitted

us-gaap:PurchaseObligation

us-gaap:PurchaseObligationDueInNextTwelveMonths

us-gaap:PurchaseObligationFutureMinimumPaymentsRemainderOfFiscalYear

us-gaap:RestrictedCashCurrent

us-gaap:RestrictedCashNoncurrent

us-gaap:RestructuringAndRelatedCostCostIncurredToDate1
us-gaap:PlanName
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice
us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRange
us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRange
us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRange
us-gaap:SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1
us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRange
us-gaap:SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
us-gaap:IncomeTaxAuthorityName
us-gaap:UndistributedEarningsOfForeignSubsidiaries

Plots across concepts


IncomeStatement
Net Income Loss
Expenses
Other Nonoperating Income Expense
Balance Sheet
Operating Lease Right Of Use Asset
Assets
Property Plant And Equipment Net
Current Assets
Accounts Receivable Net Current
NonCurrent Assets
Other Assets Noncurrent
PropertyPlantAndEquipmentNet
Property Plant And Equipment Net
Liabilities
Operating Lease Liability
Current Liabilities
Accrued Income Taxes Current
Stockholders Equity
Retained Earnings Accumulated Deficit
CashFlow
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInOperatingActivities
Increase Decrease In Accounts Receivable
Shares
Weighted Average Number Of Share Outstanding Basic And Diluted
OperatingLeaseLiability
Operating Lease Liability Current
NonoperatingIncomeExpense
Other Nonoperating Income Expense
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Undiscounted Excess Amount

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:CommonStockValue ██▇▇▇▇▇▇▇▇▇▇▇▇▆▆▆▆▅▅▅▅▅▅▅▄▃▃▃▂▂▁▁▁▁0.4490.4420.3990.3990.3990.3990.3990.3990.3990.3990.3990.3980.3980.3980.3850.3840.3820.380.3480.3440.3430.3430.3170.3150.3140.2750.2740.2740.2670.2190.2190.1770.1770.1770.177NANANA
 us-gaap:SharesOutstanding us-gaap:StatementEquityComponents prta:OrdinaryShare█▇▃▃▃▃▃▃▃▃▃▃▂▂▁44.91302444.17579239.92141339.92141339.91141339.91141339.89856139.89656139.89656139.86456139.86371139.86371139.83183639.82179938.482764NANANA34.752116NANANA31.744102NANANA27.388005NANANA21.856261NANANA17.679182NANANA
us-gaap:CommonStockSharesIssued ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁█▁▁44.91302444.17579239.92141339.92141339.91141339.91141339.89856139.89656139.89656139.86456139.86371139.86371139.83183639.82179938.48276438.44326138.15695937.95764934.75211634.45630934.38150134.34020831.74410231.5215531.37998627.46640727.38800527.38162426.66343721.9047821.85626117.67918217679.18217.67917.679NANANA
us-gaap:CommonStockSharesAuthorized ▄▄▄100.0100.0100.0NA100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100000.0100.0100.0NANANA
us-gaap:CommonStockSharesOutstanding ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁█▁▁44.91302444.17579239.92141339.92141339.91141339.91141339.89856139.89656139.89656139.86456139.86371139.86371139.83183639.82179938.48276438.44326138.15695937.95764934.75211634.45630934.38150134.34020831.74410231.5215531.37998627.46640727.38800527.38162426.66343721.9047821.85626117.67918217679.18217.67917.679NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding 47.414NANANA39.911NANANANANANANANANANANANANANANANANANA31.44130.79227.401NA27.3722.89822.942NA17.67917.67917.679NANANANA
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic 44.332NANANA39.911NANANANANANANANANANANANANANANANANANA31.44130.79227.401NA27.3721.95921.884NA17.67917.67917.679NANANANA
us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted NA40.25NA39.91739.91139.909NA39.89739.87239.864NA39.8539.82438.684NA38.29238.07335.758NA34.41334.35834.026NA31.44130.79227.401NANANANANA17.67917.67917.679NA14.49714.49714.497
 us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities us-gaap:EmployeeStockOption▁█1.6858.825NA8.7958.6728.412NA7.1857.1687.253NA7.2537.7195.227NA4.3874.6084.395NA4.174.1214.097NA3.3063.293.312NA0.7770.7060.39NA0.0571.5920.914NANANANA
us-gaap:EarningsPerShareBasic 0.62NA-0.77-0.77-0.66-0.59-0.54-0.49-0.4-0.52-0.56-0.62-1.5-1.26-1.24-1.37-0.46-0.99-1.41-1.26-1.18-0.81-0.76-0.73-0.59-0.55-0.48-0.480.060.82NA-0.55-0.64-0.51NANANANA
us-gaap:EarningsPerShareDiluted 0.58NA-0.77-0.77-0.66-0.59-0.54-0.49-0.4-0.52-0.56-0.62-1.5-1.26-1.24-1.37-0.46-0.99-1.41-1.26-1.18-0.81-0.76-0.73-0.59-0.55-0.48-0.480.060.78NA-0.55-0.64-0.51NANANANA
us-gaap:EarningsPerShareBasicAndDiluted NA-0.91-0.7599999999999998-0.77-0.66-0.59-0.54-0.49-0.4-0.52-0.5500000000000003-0.62-1.5-1.26-1.2500000000000004-1.37-0.46-0.99-1.4100000000000001-1.26-1.18-0.81-0.7700000000000002-0.73-0.59-0.55NANANANA-0.52-0.55-0.64-0.51-0.82-0.6-0.67-0.75
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
 TTM Greenblatt ROC _ _█▃▄▃▄▄▄▄▄▄▄▄▁▂▂▂▄▃▂▃▃▄▄▄▄▅▅▅▆▇▅▅▅▅▅27.949-32.109-30.308-30.846-26.732-24.848-23.274-20.972-18.497-22.954-22.755-24.323-63.069-48.708-47.317-53.534-18.132-36.271-49.277-42.688-40.16-27.41-24.212-22.661-18.035-15.029-13.105-13.1321.56918.019-10.702-9.566-11.192-8.967-12.22NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:GeneralAndAdministrativeExpense ▅▆▅▅▅▅▄▄▄▅▄▅▅▇▇▆▅▅▅█▄▄▃▃▃▂▂▂▂▂▃▂▂▂▁▁▁▁11.03211.1259.9089.3989.6569.7418.0598.6919.0819.9058.0269.23510.99214.22914.04412.43810.91210.8329.60416.1368.1347.1826.6295.9055.5225.0495.0114.234.9374.8735.2693.3893.2123.1812.9622.0822.4272.458
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments █▃▃▃▄▄▄▄▅▄▄▄▁▂▂▂▄▃▂▂▃▄▄▄▄▅▅▅▆▇▅▅▅▅▅▅▅▅27.896-32.075-30.363-30.792-26.537-23.735-21.685-18.98-15.966-20.667-21.91-23.597-61.828-48.78-47.471-54.099-18.988-37.045-48.55-42.818-40.256-27.34-24.155-22.738-18.082-14.936-12.987-12.9411.58618.003-10.906-9.552-11.178-8.945-12.215-8.668-9.711-10.811
us-gaap:IncomeTaxExpenseBenefit ▃█▃▃▃▃▃▄▃▃▄▄▁▃▃▁▂▁▃▄▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃0.2544.660.353-0.215-0.255-0.166-0.1310.468-0.1560.1980.5510.962-1.946-0.0370.287-1.705-1.287-1.70.3530.4210.1890.1810.0020.2380.1950.2660.1230.2410.2960.1510.1480.1370.1240.0060.0060.0NANA
us-gaap:IncomeTaxesPaidNet ▃▅█▄▁▅▅▅█▂0.1660.4020.6950.2550.00.4170.380.4450.7010.054NANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:InterestIncomeExpenseNet ▂▂▂▂▂▅▆▇██▄▄▄▂▂▂▂▁▂▂▂▃▂▂▂0.0080.0110.010.0430.1791.1371.5692.0342.2962.3040.870.7910.8310.20.0860.1180.018-0.3640.1510.138-0.010.2770.080.050.04NANANANANANANANANANANANANA
us-gaap:NetIncomeLoss █▃▃▃▄▄▄▄▅▄▄▄▁▂▂▂▄▃▂▂▃▄▄▄▄▅▅▅▆▇▅▅▅▅▅▅▅▅27.642-36.735-30.716-30.577-26.282-23.569-21.554-19.448-15.81-20.865-22.461-24.559-59.882-48.743-47.758-52.394-17.701-35.384-48.903-43.239-40.445-27.521-24.157-22.976-18.277-15.202-13.11-13.1821.2917.852-11.054-9.689-11.302-8.951-12.221-8.668-9.711-10.811
us-gaap:NonoperatingIncomeExpense ▃▃▃▃▃▅▆▇█▇▅▄▅▃▂▂▁▁▄▃▃▃▃▃▃▃▃▃▃▃▂▃▃▃-0.0530.034-0.0550.0540.1951.1131.5891.9922.5312.2870.8450.7261.241-0.072-0.154-0.565-0.856-0.7740.727-0.13-0.0960.070.057-0.077-0.0470.0930.1180.1910.017-0.016-0.2040.0140.0140.022NANANANA
us-gaap:OperatingExpenses ▄▄▄▄▃▃▃▃▂▃▃▃█▆▆▇▆▅▆▅▅▃▃▃▂▂▂▂▂▂▁▁▁▁▁▁▁▁32.12232.26930.66831.00326.92724.98923.5321.17718.66423.1422.94924.57863.34848.93547.54653.75344.94436.5349.44842.97440.49327.67524.51923.0918.31315.62215.11814.61813.55214.21510.8699.73711.3599.13812.7959.61210.44611.215
us-gaap:OperatingIncomeLoss █▃▄▃▄▄▄▄▄▄▄▄▁▂▂▂▄▃▂▃▃▄▄▄▄▅▅▅▆▇▅▅▅▅▅▅▅▅27.949-32.109-30.308-30.846-26.732-24.848-23.274-20.972-18.497-22.954-22.755-24.323-63.069-48.708-47.317-53.534-18.132-36.271-49.277-42.688-40.16-27.41-24.212-22.661-18.035-15.029-13.105-13.1321.56918.019-10.702-9.566-11.192-8.967-12.22-8.668-9.711-10.811
us-gaap:OtherNonoperatingIncomeExpense ▅▅▅▅▅▅▅▅▆▅▅▅▇▄▄▂▁▃█▄▅▄▅▅▅▆▆▆▅▅▄▅▅▅-0.0610.023-0.0650.0110.016-0.0240.02-0.0420.235-0.017-0.025-0.0650.41-0.272-0.24-0.683-0.874-0.410.576-0.268-0.086-0.207-0.023-0.127-0.0870.0670.0930.1720.001-0.035-0.2250.00.00.0NANANANA
us-gaap:ResearchAndDevelopmentExpense ▄▄▄▄▃▃▃▂▂▃▃▄▆▇▆█▇▅█▅▆▄▃▃▂▂▂▂▂▂▁▁▁▁▂▁▁▂21.0921.14420.7621.60517.27115.24815.47112.4869.58313.29616.5118.51531.45234.70633.50241.31534.03225.69839.84426.83832.35920.49317.8917.18512.79110.57310.10710.3888.6159.3425.66.3488.1475.9579.8337.538.0198.757
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax █▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▄▁▁▁▁▁▁▁▁▁▁▁▃▅▁▁▁▁▁▁▁▁60.0710.160.360.1570.1950.1410.2560.2050.1670.1860.1940.2550.2790.2270.2290.21926.8120.2590.1710.2860.3330.2650.3070.4290.2780.5932.0131.48615.12132.2340.1670.1710.1670.1710.5750.9440.7350.404
us-gaap:Revenues █▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▄▁▁▁▁▁▁▁▁▁▁▁▃▅▁▁▁▁▁▁▁▁60.0710.160.360.1570.1950.1410.2560.2050.1670.1860.1940.2550.2790.2270.2290.21926.8120.2590.1710.2860.3330.2650.3070.4290.2780.5932.0131.48615.12132.2340.1670.1710.1670.1710.5750.9440.7350.404
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:Assets ▆▅▄▄▅▅▅▆▆▆▆▇▇█▆▇██▆▆▇▆▅▅▅▄▄▄▄▂▂▁▁▁▁436.378379.719332.975355.784378.933399.421419.268450.894462.072459.534498.796524.626563.3606.647496.329537.68579.0581.95459.976479.582502.562491.308385.236398.93411.164289.585304.116313.597311.685203.81182.41107.936117.93124.268129.283NANANA
us-gaap:Liabilities ▆▆▆▆▆▆▆▆▆▆▇▇██▄▄▄▄▄▄▃▂▂▂▁▁▁▁▁▁▁▁▁▁▁148.171145.135148.969146.27144.489144.382146.347161.719159.265147.404175.798184.976207.294197.14289.1491.42692.02485.70294.57378.48271.69725.52824.56720.97715.94412.15914.22712.03613.26610.7999.149.15510.7016.4792.799NANANA
us-gaap:LiabilitiesAndStockholdersEquity ▆▅▄▄▅▅▅▆▆▆▆▇▇█▆▇██▆▆▇▆▅▅▅▄▄▄▄▂▂▁▁▁▁436.378379.719332.975355.784378.933399.421419.268450.894462.072459.534498.796524.626563.3606.647496.329537.68579.0581.95459.976479.582502.562491.308385.236398.93411.164289.585304.116313.597311.685203.81182.41107.936117.93124.268129.283NANANA
us-gaap:StockholdersEquity ▄▃▃▃▃▄▄▄▅▅▅▅▆▆▆▇██▆▆▇▇▆▆▆▄▄▅▅▃▂▁▁▁▁288.207234.584184.006209.514234.444255.039272.921289.175302.807312.13322.998339.65356.006409.505407.189446.254486.976496.248365.403401.1430.865465.78360.669377.953395.22277.426289.889301.561298.419193.011173.2798.781107.229117.789126.484NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:AssetsCurrent ▆▅▄▅▅▅▅▆▆▆▆▇▇█▆▇██▆▆▇▇▅▆▆▄▄▄▄▃▂▁▁▁▁409.468352.301299.284320.485341.123359.691378.375409.202418.708415.193431.39456.908494.037537.153426.327469.064511.72514.204391.362415.638450.598482.092377.403393.576406.2284.419299.275308.819307.019199.598178.222102.938113.594120.791125.841NANANA
us-gaap:CashAndCashEquivalentsAtCarryingValue ▇▆▅▅▆▆▆▆▇▇▇▇█▇▇▇██▆▇▇█▆▆▇▅▅▅▅▄▃▂▃▃▃▁399.831342.993295.38314.525333.942352.685375.723390.304398.144410.106427.659451.512486.212429.039417.62456.061471.729506.55386.923408.574442.948474.252370.586387.802402.389279.857293.579306.153303.851195.052176.677101.859112.507119.563124.860.0NANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▄▃▁▂▂▃▄▄▄▅▅▆▇▅▅▆▇█▄▅▆402.535345.697298.084317.229336.646355.389378.427393.008402.2414.162431.715455.568490.268433.095421.676460.117475.785510.606390.979412.63447.004NA370.586NANANA293.579NANANANANANANANANANANA
us-gaap:AccountsReceivableNetCurrent ▁▁▂▂▃█▄0.0030.0010.0150.0220.0560.1740.068NANANA0.0020.00.0080.0120.240.2230.240.2710.1780.4090.3641.0030.5090.8140.9611.3571.7290.9671.4912.1610.0NANANANANANANA
us-gaap:PrepaidExpenseAndOtherAssetsCurrent ▄▄▂▂▃▃▂██▂▂▃▄▄▄▆▄▄▂▃▃▃▃▃▂▂▂▁▁▂▁▁▁▁▁8.2827.9552.5374.5867.1256.8322.65218.89819.2123.7353.7295.3967.8178.1028.46712.7839.7517.3834.2616.6557.2866.8376.3084.7862.6853.0123.771.5181.5492.2621.4060.7580.9590.8940.685NANANA
us-gaap:MachineryAndEquipmentGross ▇▇▇▇▇▇▇▇▇▇█▇▇▇▇▇▇▇█▅▂▂▂▁▁▁▁▂▁▁▁▁▁▁▁9.359.359.3439.3439.3349.3349.3129.3199.2429.2129.6939.1379.0849.0849.0789.0519.028.8029.6298.096.3236.3116.215.6535.5575.5055.4815.7895.7355.665.6495.6225.6335.6975.449NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:AssetsNoncurrent ▃▄▄▄▅▅▅▅▅▅█████████▇▆▂▁▁▁▁▁▁▁▁▁▁▁▁▁26.9127.41833.69135.29937.8139.7340.89341.69243.36444.34167.40667.71869.26369.49470.00268.61667.2867.74668.61463.94451.9649.2167.8335.3544.9645.1664.8414.7784.6664.2124.1884.9984.3363.4773.442NANANA
us-gaap:PropertyPlantAndEquipmentGross ▂▂▂▂▂▂▂▂▂▂█████████▇▆▁▁▁▁▁▁▁▁▁▁▁▁▁▁12.16812.09212.04412.04811.98711.92211.88111.86711.56211.48963.33963.06962.72262.81862.73362.37762.07461.67364.1258.58247.8669.5189.2058.0667.9157.867.8328.127.9867.6977.6617.6347.6387.217.1NANANA
us-gaap:LeaseholdImprovementsGross ▄▄▄▄▄▄▄▄▃▃▁▃▂▂▂▂▂▂▇▇▇█▇▆▆▆▆▆▆▅▅▅▅▄▅1.3941.3181.2781.2611.2611.2611.2611.2451.0170.9740.0980.8220.5790.5790.5790.5790.580.582.7692.772.7643.042.8282.2542.222.2172.2142.2112.1311.9271.9271.9271.921.5131.651NANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment █▇▇▇▆▆▅▅▅▄██▇▆▅▄▄▃▅▄▃▃▃▂▂▂▂▂▂▂▂▁▁▁▁10.0889.7979.4939.1498.7728.3918.0077.6227.2446.85710.50410.1189.3248.547.7436.9936.2315.5897.6686.8446.0145.5945.3435.1365.0994.9044.7114.8384.6464.4644.2894.0533.9093.8393.707NANANA
us-gaap:PropertyPlantAndEquipmentNet ▁▁▁▁▁▁▁▁▁▁█████████▇▆▁▁▁▁▁▁▁▁▁▁▁▁▁▁2.082.2952.5512.8993.2153.5313.8744.2454.3184.63252.83552.95153.39854.27854.9955.38455.84356.08456.45251.73841.8523.9243.8622.932.8162.9563.1213.2823.343.2333.3723.5813.7293.3713.393NANANA
us-gaap:DeferredTaxAssetsLiabilitiesNet NANA11.644NANANA9.956NANANA9.702NANANA8.113NANANA5.913NANANA2.85NANANA1.887NANANA0.897NANANA0.073NANANA
us-gaap:OperatingLeaseRightOfUseAsset ▅▅▆▆▆▇▇▇██▁14.99616.41117.81119.19720.5721.92923.27424.60725.92727.2340.0NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent ▆▂▂▂▂▄▄▃▃▃▃▂▂███▅▇▆▆▇▆▄▁2.0510.3380.3330.3270.3041.1151.0850.6770.9230.8680.8130.5020.5022.842.8432.7841.6252.432.1932.1622.3631.9981.1210.007NA0.1170.0NA0.028NA0.00.739NANA0.0NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:AccountsPayableCurrent ▄▃▃▂▂▂▁▂▁▂▁▃▆▇█▇▇▄█▆▇▅▃▃▂▂▃▁▁▂▁▁5.9084.2124.1172.812.1243.2971.2422.4181.5252.1031.474.48510.05211.5913.63311.06212.5456.25413.06910.5411.5927.8974.5194.0582.8651.994.7221.241.4832.1281.790.896NANA0.0NANANA
us-gaap:AccruedIncomeTaxesCurrent NANA0.0360.2580.2210.00.0050.0120.0220.290.0540.2850.9460.4810.3110.0530.4040.3850.3781.18NA0.530.00.00.00.00.0570.2820.4060.00.1840.6170.30.0720.027NANANA
us-gaap:LiabilitiesCurrent █▄▄▄▃▃▃▅▅▃▃▄▇▆▆▆▆▅▆▆▅▄▄▃▃▂▂▂▂▂▂▂▂▁▁52.89923.45625.84821.72218.54417.08617.71431.76328.01614.90614.92623.62746.13235.55537.37139.25839.59933.6841.07536.90833.45623.23422.21618.55813.4569.54412.0399.97111.3118.9647.4067.7159.0835.0861.744NANANA
us-gaap:OperatingLeaseLiabilityCurrent ████▇▇▇▇▇▇▁5.7235.6175.5125.4085.3045.2025.1015.0024.9044.810.0NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherLiabilitiesCurrent ▃▂▃▃▂▂▂██▁▃▂▂▃▄▄▃▂▄▄▂▂▂▂▂▂▂▂▂▁▂▂▁▁▁7.9444.2727.1395.6294.7433.3645.5420.07819.3052.9655.9265.4245.1046.6919.1859.2895.8515.3318.5558.2515.2143.8374.9034.9784.1923.8924.9753.8143.6922.4773.893.0852.3062.4181.67NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:LiabilitiesNoncurrent ▅▆▆▆▆▆▇▇▇▇████▃▃▃▃▃▃▃▁▁▁▁▁▁▁▁95.272121.679123.121124.548125.945127.296128.633129.956131.249132.498160.872161.349161.162161.58751.76952.16852.42552.02253.49841.57438.2412.2942.3512.4192.4882.6152.1882.0651.955NA1.734NANANANANANANA
us-gaap:OtherLiabilitiesNoncurrent ▄▄▄▄▄▄▄▄▄▄▄▄0.5530.5530.5530.5530.5530.5530.5530.5530.5530.5530.5530.553NANA0.0NANANA0.00.00.1260.1260.1260.1260.1260.1260.0NANANANANANANANANANANA
us-gaap:OperatingLeaseLiabilityNoncurrent ▄▅▅▅▆▆▇▇██▁9.42610.88412.32613.75315.1516.50117.83819.16120.45421.7030.0NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo ██▄▁6.5356.5356.356.191NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree NANA6.5356.35NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour NANANA6.535NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:StockholdersEquity ▄▃▃▃▃▄▄▄▅▅▅▅▆▆▆▇██▆▆▇▇▆▆▆▄▄▅▅▃▂▁▁▁▁288.207234.584184.006209.514234.444255.039272.921289.175302.807312.13322.998339.65356.006409.505407.189446.254486.976496.248365.403401.1430.865465.78360.669377.953395.22277.426289.889301.561298.419193.011173.2798.781107.229117.789126.484NANANA
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest ▄▃▁▂▃▃▄▄▅▅▅▆▆██288.207234.584184.006209.514234.444255.039272.921289.175302.807312.13322.998339.65356.006409.505407.189NANANA365.403NANANA360.669NANANA289.889NANANA173.27NANANA126.484NANANA
us-gaap:CommonStockValue ██▇▇▇▇▇▇▇▇▇▇▇▇▆▆▆▆▅▅▅▅▅▅▅▄▃▃▃▂▂▁▁▁▁0.4490.4420.3990.3990.3990.3990.3990.3990.3990.3990.3990.3980.3980.3980.3850.3840.3820.380.3480.3440.3430.3430.3170.3150.3140.2750.2740.2740.2670.2190.2190.1770.1770.1770.177NANANA
us-gaap:AdditionalPaidInCapital ██▇▇▇▇▇▇▇▇▇▇▇▇▆▆▆▆▅▅▅▅▄▄▄▃▃▃▂▂▂▁▁▁▁1079.881053.906966.636961.428955.781950.094944.407939.107933.291926.804920.594914.786906.583900.2849.154840.462828.792820.365654.266641.064627.591622.061489.455482.584476.876340.844338.106336.668320.351216.281214.392128.891127.65126.908126.652NANANA
us-gaap:RetainedEarningsAccumulatedDeficit ▁▁▁▂▂▂▂▂▃▃▃▃▃▄▄▅▅▅▆▆▆▇▇▇▇▇█████████-792.122-819.764-783.029-752.313-721.736-695.454-671.885-650.331-630.883-615.073-597.995-575.534-550.975-491.093-442.35-394.592-342.198-324.497-289.211-240.308-197.069-156.624-129.103-104.946-81.97-63.693-48.491-35.381-22.199-23.489-41.341-30.287-20.598-9.296-0.345NANANA
us-gaap:StockIssuedDuringPeriodValueNewIssues NA78.054NANANANANANANANA0.00.00.039.758NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents prta:OrdinaryShareNA0.04NANANANANANANANA0.00.00.00.012NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents us-gaap:AdditionalPaidInCapitalNA78.014NANANANANANANANA0.00.00.039.746NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents,us-gaap:SubsidiarySaleOfStock prta:OrdinaryShare,prta:AtTheMarketOffering0.003NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents,us-gaap:SubsidiarySaleOfStock prta:OrdinaryShare,prta:UnderwrittenPublicOfferingNA78.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents,us-gaap:SubsidiarySaleOfStock us-gaap:AdditionalPaidInCapital,prta:AtTheMarketOffering13.964NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:SubsidiarySaleOfStock prta:AtTheMarketOffering13.967NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue ▁█5.546.176NANA5.6875.5365.2875.8166.2776.2055.8097.0426.3096.902NANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▆▁▂▂▂▂▃▃▃▃▂▁█▂▁▃▁▁▁▂▂▂▂▃▃▃▃▃▄▅▃▃▃▃▃▃▃▃36.619-33.666-19.094-19.404-18.697-23.167-14.488-8.943-12.103-17.435-21.252-33.57358.133-31.584-39.524-17.738-36.079-37.842-33.998-30.588-27.53-25.153-19.681-16.914-11.14-14.72-12.523-12.2656.21117.894-9.836-10.304-6.855-5.103-15.635-7.449-10.364-8.624
us-gaap:NetCashProvidedByUsedInInvestingActivities ██████████▇██████▆▅▁▄█▇███████████▇███0.0-0.048-0.051-0.077-0.046-0.022-0.106-0.249-0.069-0.123-1.297-0.152-0.099-0.181-0.376-0.538-0.208-2.399-3.091-8.555-4.76-0.238-0.985-0.329-0.04-0.028-0.04-0.106-0.327-0.0260.003-0.227-0.201-0.11-1.027-0.103-0.034-0.137
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▅▁▁▁▁▁▁▁▁▁▁▁▃▁▁▁█▂▁▁▇▁▁▇▁▁▂▆▁▅▁▁▁▇▁▂▁20.21981.3270.00.0640.00.1510.0130.00.210.005-1.304-0.975-0.86143.1841.4592.6081.466159.86819.4944.7690.986129.0573.452.656133.7121.026-0.01114.673102.9150.50784.651-0.1170.0-0.084141.5227.55210.3988.761
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect NANANA-19.417-18.743-23.038NA-9.192-11.962-17.553NANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:DepreciationDepletionAndAmortization ▃▃▃▄▄▄▄▄▄▄▇▇▇▇▇▇▇▇█▇▄▂▂▂▂▂▂▂▂▂▂▁▂▁▂▁▁▁0.2910.3040.3620.3870.3810.3840.40.3920.3870.3850.8260.7940.7990.7970.7820.7670.7590.7590.9180.830.4280.2510.2180.20.1950.1930.1940.20.20.1750.2320.10.20.1370.1620.0780.1150.113
us-gaap:IncreaseDecreaseInAccountsReceivable ▅▄▄▄▁█0.002-0.014-0.007-0.034-0.1180.106NA0.0-0.0070.0050.002-0.008-100.00499.7720.02-30.0229.9690.093-0.2310.045-0.6390.494-0.305-0.147-0.396-0.3720.762-0.524-0.672.1610.00.00.00.0NANANANA
us-gaap:NetCashProvidedByUsedInOperatingActivities ▆▁▂▂▂▂▃▃▃▃▂▁█▂▁▃▁▁▁▂▂▂▂▃▃▃▃▃▄▅▃▃▃▃▃▃▃▃36.619-33.666-19.094-19.404-18.697-23.167-14.488-8.943-12.103-17.435-21.252-33.57358.133-31.584-39.524-17.738-36.079-37.842-33.998-30.588-27.53-25.153-19.681-16.914-11.14-14.72-12.523-12.2656.21117.894-9.836-10.304-6.855-5.103-15.635-7.449-10.364-8.624
us-gaap:NetIncomeLoss █▃▃▃▄▄▄▄▅▄▄▄▁▂▂▂▄▃▂▂▃▄▄▄▄▅▅▅▆▇▅▅▅▅▅▅▅▅27.642-36.735-30.716-30.577-26.282-23.569-21.554-19.448-15.81-20.865-22.461-24.559-59.882-48.743-47.758-52.394-17.701-35.384-48.903-43.239-40.445-27.521-24.157-22.976-18.277-15.202-13.11-13.1821.2917.852-11.054-9.689-11.302-8.951-12.221-8.668-9.711-10.811
us-gaap:ShareBasedCompensation ▄▅▄▄▄▄▄▄▅▅▃▅▆▅▅▅▅▄▄█▄▃▃▃▂▂▂▂▂▂▁▁▁▁▁▁▂▃5.546.1765.2085.5835.6875.5365.2875.8166.2776.2054.2457.0428.8216.9027.4077.1026.6535.6025.21111.4484.5463.7243.2783.0172.4161.7031.3981.4181.4381.3431.0910.9550.7420.340.3650.5081.6553.57
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ██████████▇██████▆▅▁▄█▇███████████▇███0.0-0.048-0.051-0.077-0.046-0.022-0.106-0.249-0.069-0.123-1.297-0.152-0.099-0.181-0.376-0.538-0.208-2.399-3.091-8.555-4.76-0.238-0.985-0.329-0.04-0.028-0.04-0.106-0.327-0.0260.003-0.227-0.201-0.11-1.027-0.103-0.034-0.137
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▅▁▁▁▁▁▁▁▁▁▁▁▃▁▁▁█▂▁▁▇▁▁▇▁▁▂▆▁▅▁▁▁▇▁▂▁20.21981.3270.00.0640.00.1510.0130.00.210.005-1.304-0.975-0.86143.1841.4592.6081.466159.86819.4944.7690.986129.0573.452.656133.7121.026-0.01114.673102.9150.50784.651-0.1170.0-0.084141.5227.55210.3988.761
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value449000.0442000.0399000.0399000.0399000.0399000.0399000.0399000.0399000.0399000.0399000.0398000.0398000.0398000.0385000.0384000.0382000.0380000.0348000.0344000.0343000.0343000.0317000.0315000.0314000.0275000.0274000.0274000.0267000.0219000.0219000.0177000.0177000.0177000.0177000.0
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.20.20.10.1

Shares Outstanding

us-gaap:SharesOutstanding us-gaap:StatementEquityComponents

us-gaap:SharesOutstanding

prta:OrdinaryShare


Shares
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value44443939393939393939393939393834312721170.00.0
Percentage of SharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

Common Stock Shares Issued

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesIssued


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value4444393939393939393939393939383838373434343431313127272726212117176791717
Percentage of CommonStockSharesIssued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Authorized

us-gaap:CommonStockSharesAuthorized

us-gaap:CommonStockSharesAuthorized


Common
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value100100100100100100100100100100100100100100100100100100100100100100100100100100100100100100100100000100100
Percentage of CommonStockSharesAuthorized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStockSharesOutstanding


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value4444393939393939393939393939383838373434343431313127272726212117176791717
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2021-06-302020-06-302015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value4739313027272222171717
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2021-06-302020-06-302015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value4439313027272121171717
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Share Outstanding Basic And Diluted

us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted

us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted


Weighted
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-31
Value40393939393939393938383835343434313027171717141414
Percentage of WeightedAverageNumberOfShareOutstandingBasicAndDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:EmployeeStockOption


Antidilutive
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value1685000.08825000.08795000.08672000.08412000.07185000.07168000.07253000.07253000.07719000.05227000.04387000.04608000.04395000.04170000.04121000.04097000.03306000.03290000.03312000.0777000.0706000.0390000.057000.01592000.0914000.0
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value0.62-0.77-0.77-0.66-0.59-0.54-0.49-0.4-0.52-0.56-0.62-1.5-1.26-1.24-1.37-0.46-0.99-1.41-1.26-1.18-0.81-0.76-0.73-0.59-0.55-0.48-0.480.060.82-0.55-0.64-0.51
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value0.58-0.77-0.77-0.66-0.59-0.54-0.49-0.4-0.52-0.56-0.62-1.5-1.26-1.24-1.37-0.46-0.99-1.41-1.26-1.18-0.81-0.76-0.73-0.59-0.55-0.48-0.480.060.78-0.55-0.64-0.51
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic And Diluted

us-gaap:EarningsPerShareBasicAndDiluted

us-gaap:EarningsPerShareBasicAndDiluted


Earnings
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-0.91-0.76-0.77-0.66-0.59-0.54-0.49-0.4-0.52-0.55-0.62-1.5-1.26-1.25-1.37-0.46-0.99-1.41-1.26-1.18-0.81-0.77-0.73-0.59-0.55-0.52-0.55-0.64-0.51-0.82-0.6-0.67-0.75
Percentage of EarningsPerShareBasicAndDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

General And Administrative Expense

us-gaap:GeneralAndAdministrativeExpense

us-gaap:GeneralAndAdministrativeExpense


General
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value11119.9089.3989.6569.7418.0598.6919.0819.9058.0269.2351014141210109.604168.1347.1826.6295.9055.5225.0495.0114.234.9374.8735.2693.3893.2123.1812.9622.0822.4272.458
Percentage of GeneralAndAdministrativeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax18.46953.12752.25986.04951.86908.53148.04239.55437.75325.34137.13621.63939.86268.36132.85679.540.74182.25616.45642.02442.62710.22159.31376.51986.3851.4248.9284.732.615.13155.11981.91923.41860.2515.1220.6330.2608.4

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value27-32.075-30.363-30.792-26.537-23.735-21.685-18.98-15.966-20.667-21.91-23.597-61.828-48.78-47.471-54.099-18.988-37.045-48.55-42.818-40.256-27.34-24.155-22.738-18.082-14.936-12.987-12.9411.58618-10.906-9.552-11.178-8.945-12.215-8.668-9.711-10.811
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.4-20046.9-8434.2-19612.7-13608.7-16833.3-8470.7-9258.5-9560.5-11111.3-11293.8-9253.7-22160.6-21489.0-20729.7-24702.7-70.8-14303.1-28391.8-14971.3-12088.9-10317.0-7868.1-5300.2-6504.3-2518.7-645.2-870.910.555.9-6530.5-5586.0-6693.4-5231.0-2124.3-918.2-1321.2-2676.0

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxExpenseBenefit


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value254000.04660000.0353000.0-215000.0-255000.0-166000.0-131000.0468000.0-156000.0198000.0551000.0962000.0-1946000.0-37000.0287000.0-1705000.0-1287000.0-1700000.0353000.0421000.0189000.0181000.02000.0238000.0195000.0266000.0123000.0241000.0296000.0151000.0148000.0137000.0124000.06000.06000.00
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.42912.598.1-136.9-130.8-117.7-51.2228.3-93.4106.5284.0377.3-697.5-16.3125.3-778.5-4.8-656.4206.4147.256.868.30.755.570.144.96.116.22.00.588.680.174.33.51.00.0

Income Taxes Paid Net

us-gaap:IncomeTaxesPaidNet

us-gaap:IncomeTaxesPaidNet


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value166000.0402000.0695000.0255000.00417000.0380000.0445000.0701000.054000.0
Percentage of IncomeTaxesPaidNet100.0100.0100.0100.00.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.3251.3193.1162.40.0295.7148.4217.1419.829.0

Interest Income Expense Net

us-gaap:InterestIncomeExpenseNet

us-gaap:InterestIncomeExpenseNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value8000.011000.010000.043000.0179000.01137000.01569000.02034000.02296000.02304000.0870000.0791000.0831000.0200000.086000.0118000.018000.0-364000.0151000.0138000.0-10000.0277000.080000.050000.040000.0
Percentage of InterestIncomeExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.06.92.827.491.8806.4612.9992.21374.91238.7448.5310.2297.888.137.653.90.1-140.588.348.3-3.0104.526.111.714.4

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value27-36.735-30.716-30.577-26.282-23.569-21.554-19.448-15.81-20.865-22.461-24.559-59.882-48.743-47.758-52.394-17.701-35.384-48.903-43.239-40.445-27.521-24.157-22.976-18.277-15.202-13.11-13.1821.2917-11.054-9.689-11.302-8.951-12.221-8.668-9.711-10.811
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.0-22959.4-8532.2-19475.8-13477.9-16715.6-8419.5-9486.8-9467.1-11217.7-11577.8-9631.0-21463.1-21472.7-20855.0-23924.2-66.0-13661.8-28598.2-15118.5-12145.6-10385.3-7868.7-5355.7-6574.5-2563.6-651.3-887.18.555.4-6619.2-5666.1-6767.7-5234.5-2125.4-918.2-1321.2-2676.0

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value27-36.735-30.716-30.577-26.282-23.569-21.554-19.448-15.81-20.865-22.461-24.559-59.882-48.743
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.0-22959.4-8532.2-19475.8-13477.9-16715.6-8419.5-9486.8-9467.1-11217.7-11577.8-9631.0-21463.1-21472.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Nonoperating Income Expense

us-gaap:NonoperatingIncomeExpense

us-gaap:NonoperatingIncomeExpense


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-53000.034000.0-55000.054000.0195000.01113000.01589000.01992000.02531000.02287000.0845000.0726000.01241000.0-72000.0-154000.0-565000.0-856000.0-774000.0727000.0-130000.0-96000.070000.057000.0-77000.0-47000.093000.0118000.0191000.017000.0-16000.0-204000.014000.014000.022000.0
Percentage of NonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.121.2-15.334.4100.0789.4620.7971.71515.61229.6435.6284.7444.8-31.7-67.2-258.0-3.2-298.8425.1-45.5-28.826.418.6-17.9-16.915.75.912.90.1-0.0-122.28.28.412.9

Operating Expenses

us-gaap:OperatingExpenses

us-gaap:OperatingExpenses


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value323230312624232118232224634847534436494240272423181515141314109.737119.138129.6121011
Percentage of OperatingExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax53.520168.18518.919747.113808.717722.79191.410330.211176.012440.911829.49638.422705.421557.320762.424544.7167.614104.228917.015025.912160.110443.47986.65382.36587.42634.4751.0983.789.644.16508.45694.26801.85343.92225.21018.21421.22776.0

Operating Income Loss

us-gaap:OperatingIncomeLoss

us-gaap:OperatingIncomeLoss


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value27-32.109-30.308-30.846-26.732-24.848-23.274-20.972-18.497-22.954-22.755-24.323-63.069-48.708-47.317-53.534-18.132-36.271-49.277-42.688-40.16-27.41-24.212-22.661-18.035-15.029-13.105-13.1321.56918-10.702-9.566-11.192-8.967-12.22-8.668-9.711-10.811
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.5-20068.1-8418.9-19647.1-13708.7-17622.7-9091.4-10230.2-11076.0-12340.9-11729.4-9538.4-22605.4-21457.3-20662.4-24444.7-67.6-14004.2-28817.0-14925.9-12060.1-10343.4-7886.6-5282.3-6487.4-2534.4-651.0-883.710.455.9-6408.4-5594.2-6701.8-5243.9-2125.2-918.2-1321.2-2676.0

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:OtherNonoperatingIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-61000.023000.0-65000.011000.016000.0-24000.020000.0-42000.0235000.0-17000.0-25000.0-65000.0410000.0-272000.0-240000.0-683000.0-874000.0-410000.0576000.0-268000.0-86000.0-207000.0-23000.0-127000.0-87000.067000.093000.0172000.01000.0-35000.0-225000.0000
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.114.4-18.17.08.2-17.07.8-20.5140.7-9.1-12.9-25.5147.0-119.8-104.8-311.9-3.3-158.3336.8-93.7-25.8-78.1-7.5-29.6-31.311.34.611.60.0-0.1-134.70.00.00.0

Research And Development Expense

us-gaap:ResearchAndDevelopmentExpense

us-gaap:ResearchAndDevelopmentExpense


Research
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value21212021171515129.583131618313433413425392632201717121010108.6159.3425.66.3488.1475.9579.8337.538.0198.757
Percentage of ResearchAndDevelopmentExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax35.113215.05766.713761.18856.910814.26043.46090.75738.37148.48510.37260.811273.115289.014629.718865.3126.99922.023300.69383.99717.47733.25827.44005.84601.11783.0502.1699.157.029.03353.33712.34878.43483.61710.1797.71091.02167.6

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value600.160.360.1570.1950.1410.2560.2050.1670.1860.1940.2550.2790.2270.2290.219260.2590.1710.2860.3330.2650.3070.4290.2780.5932.0131.48615320.1670.1710.1670.1710.5750.9440.7350.404
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService

prta:Collaboration


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value600.110.1210.1570.1450.1410.2560.2050.167
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.068.833.6100.074.4100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.068.833.6100.074.4100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax prta:Collaboration100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:License


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-06-30
Value0.00.050.2390.00.050.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.031.266.40.025.60.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.031.266.40.025.60.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:License0.0100.0100.00.0100.00.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value600.160.360.1570.1950.1410.2560.2050.1670.1860.1940.2550.2790.2270.2290.219260.2590.1710.2860.3330.2650.3070.4290.2780.5932.0131.48615320.1670.1710.1670.1710.5750.9440.7350.404
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value436379332355378399419450462459498524563606496537579581459479502491385398411289304313311203182107117124129
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities

us-gaap:Liabilities

us-gaap:Liabilities


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value148145148146144144146161159147175184207197899192859478712524201512141213109.149.155106.4792.799
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets34.038.244.741.138.136.134.935.934.532.135.235.336.832.518.017.015.914.720.616.414.35.26.45.33.94.24.73.84.35.35.08.59.15.22.2

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value436379332355378399419450462459498524563606496537579581459479502491385398411289304313311203182107117124129
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value28823418420923425527228930231232233935640940744648649636540143046536037739527728930129819317398107117126
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets66.061.855.358.961.963.965.164.165.567.964.864.763.267.582.083.084.185.379.483.685.794.893.694.796.195.895.396.295.794.795.091.590.994.897.8

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value409352299320341359378409418415431456494537426469511514391415450482377393406284299308307199178102113120125
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets93.892.889.990.190.090.190.290.890.690.486.587.187.788.585.987.288.488.485.186.789.798.198.098.798.898.298.498.598.597.997.795.496.397.297.3

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-312010-12-31
Value3993422953143333523753903984104274514864294174564715063864084424743703874022792933063031951761011121191240.00.00.0
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0
Percentage of Assets91.690.388.788.488.188.389.686.686.289.285.786.186.370.784.184.881.587.084.185.288.196.596.297.297.996.696.597.697.595.796.994.495.496.296.60.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value402345298317336355378393402414431455490433421460475510390412447370293
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets92.291.089.589.288.889.090.387.287.090.186.686.887.071.485.085.682.287.785.086.088.996.296.5

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent

us-gaap:AccountsReceivableNetCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value0.0030.0010.0150.0220.0560.1740.0680.0020.00.0080.0120.240.22300.2710.1780.4090.3641.0030.5090.8140.9611.3571.7290.9671.4912.1610.0
Percentage of AccountsReceivableNetCurrent100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.05.20.00.00.10.10.20.10.20.20.50.60.30.51.10.0

us-gaap:AccountsReceivableNetCurrent us-gaap:CounterpartyName, us-gaap:TypeOfArrangement

prta:Roche, us-gaap:CollaborativeArrangement


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.0030.0010.0030.0020.0040.0020.0020.0420.00.0070.002
Percentage of AccountsReceivableNetCurrent100.0100.020.09.17.11.12.90.00.00.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets prta:Roche us-gaap:CollaborativeArrangement0.00.00.00.00.00.00.00.00.00.00.0

Prepaid Expense And Other Assets Current

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PrepaidExpenseAndOtherAssetsCurrent


Prepaid
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value8.2827.9552.5374.5867.1256.8322.65218193.7353.7295.3967.8178.1028.467129.7517.3834.2616.6557.2866.8376.3084.7862.6853.0123.771.5181.5492.2621.4060.7580.9590.8940.685
Percentage of PrepaidExpenseAndOtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.92.10.81.31.91.70.64.24.20.80.71.01.41.31.72.41.71.30.91.41.41.41.61.20.71.01.20.50.51.10.80.70.80.70.5

Machinery And Equipment Gross

us-gaap:MachineryAndEquipmentGross

us-gaap:MachineryAndEquipmentGross


Machinery
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value9350000.09350000.09343000.09343000.09334000.09334000.09312000.09319000.09242000.09212000.09693000.09137000.09084000.09084000.09078000.09051000.09020000.08802000.09629000.08090000.06323000.06311000.06210000.05653000.05557000.05505000.05481000.05789000.05735000.05660000.05649000.05622000.05633000.05697000.05449000.0
Percentage of MachineryAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.12.52.82.62.52.32.22.12.02.01.91.71.61.51.81.71.61.52.11.71.31.31.61.41.41.91.81.81.82.83.15.24.84.64.2

Assets Noncurrent

us-gaap:AssetsNoncurrent

us-gaap:AssetsNoncurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value2627333537394041434467676969706867676863519.2167.8335.3544.9645.1664.8414.7784.6664.2124.1884.9984.3363.4773.442
Percentage of AssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.27.210.19.910.09.99.89.29.49.613.512.912.311.514.112.811.611.614.913.310.31.92.01.31.21.81.61.51.52.12.34.63.72.82.7

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value1212121211111111111163636262626262616458479.5189.2058.0667.9157.867.8328.127.9867.6977.6617.6347.6387.217.1
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.83.23.63.43.23.02.82.62.52.512.712.011.110.412.611.610.710.613.912.29.51.92.42.01.92.72.62.62.63.84.27.16.55.85.5

Leasehold Improvements Gross

us-gaap:LeaseholdImprovementsGross

us-gaap:LeaseholdImprovementsGross


Leasehold
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value1394000.01318000.01278000.01261000.01261000.01261000.01261000.01245000.01017000.0974000.098000.0822000.0579000.0579000.0579000.0579000.0580000.0580000.02769000.02770000.02764000.03040000.02828000.02254000.02220000.02217000.02214000.02211000.02131000.01927000.01927000.01927000.01920000.01513000.01651000.0
Percentage of LeaseholdImprovementsGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.30.30.40.40.30.30.30.30.20.20.00.20.10.10.10.10.10.10.60.60.50.60.70.60.50.80.70.70.70.91.11.81.61.21.3

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value109.7979.4939.1498.7728.3918.0077.6227.2446.85710109.3248.547.7436.9936.2315.5897.6686.8446.0145.5945.3435.1365.0994.9044.7114.8384.6464.4644.2894.0533.9093.8393.707
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.32.62.92.62.32.11.91.71.61.52.11.91.71.41.61.31.11.01.71.41.21.11.41.31.21.71.51.51.52.22.43.83.33.12.9

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value2.082.2952.5512.8993.2153.5313.8744.2454.3184.63252525354545555565651413.9243.8622.932.8162.9563.1213.2823.343.2333.3723.5813.7293.3713.393
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.50.60.80.80.80.90.90.90.91.010.610.19.58.911.110.39.69.612.310.88.30.81.00.70.71.01.01.01.11.61.83.33.22.72.6

us-gaap:PropertyPlantAndEquipmentNet us-gaap:StatementGeographical

country:US


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302018-12-31
Value2.082.32.62.93.23.53.94.24.31852
Percentage of PropertyPlantAndEquipmentNet100.0100.2101.9100.099.599.1100.798.9100.099.9
Percentage of Assets0.50.60.80.80.80.90.90.90.910.6
Percentage of Assets country:US0.00.00.00.00.00.00.00.00.00.0

Deferred Tax Assets Liabilities Net

us-gaap:DeferredTaxAssetsLiabilitiesNet

us-gaap:DeferredTaxAssetsLiabilitiesNet


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value119.9569.7028.1135.9132.851.8870.8970.073
Percentage of DeferredTaxAssetsLiabilitiesNet100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.52.41.91.61.30.70.60.50.1

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OperatingLeaseRightOfUseAsset


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value141617192021232425270.0
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets3.44.35.35.45.45.55.65.55.65.90.0

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssetsNoncurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-03-312014-12-312014-06-302013-12-312013-09-302012-12-31
Value2051000.0338000.0333000.0327000.0304000.01115000.01085000.0677000.0923000.0868000.0813000.0502000.0502000.02840000.02843000.02784000.01625000.02430000.02193000.02162000.02363000.01998000.01121000.07000.0117000.0028000.00739000.00
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.00.0
Percentage of Assets0.50.10.10.10.10.30.30.20.20.20.20.10.10.50.60.50.30.40.50.50.50.40.30.00.00.00.00.00.70.0

Accounts Payable Current

us-gaap:AccountsPayableCurrent

us-gaap:AccountsPayableCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value5.9084.2124.1172.812.1243.2971.2422.4181.5252.1031.474.48510111311126.2541310117.8974.5194.0582.8651.994.7221.241.4832.1281.790.8960.0
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets1.41.11.20.80.60.80.30.50.30.50.30.91.81.92.72.12.21.12.82.22.31.61.21.00.70.71.60.40.51.01.00.80.0

Accrued Income Taxes Current

us-gaap:AccruedIncomeTaxesCurrent

us-gaap:AccruedIncomeTaxesCurrent


Accrued
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value36000.0258000.0221000.005000.012000.022000.0290000.054000.0285000.0946000.0481000.0311000.053000.0404000.0385000.0378000.01180000.0530000.0000057000.0282000.0406000.00184000.0617000.0300000.072000.027000.0
Percentage of AccruedIncomeTaxesCurrent100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.10.10.00.00.00.00.10.00.10.20.10.10.00.10.10.10.20.10.00.00.00.00.00.10.10.00.10.60.30.10.0

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value522325211817173128141423463537393933413633232218139.544129.971118.9647.4067.7159.0835.0861.744
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets12.16.27.86.14.94.34.27.06.13.23.04.58.25.97.57.36.85.88.97.76.74.75.84.73.33.34.03.23.64.44.17.17.74.11.3

Operating Lease Liability Current

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OperatingLeaseLiabilityCurrent


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5723000.05617000.05512000.05408000.05304000.05202000.05101000.05002000.04904000.04810000.00
Percentage of OperatingLeaseLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets1.31.51.71.51.41.31.21.11.11.00.0

Other Liabilities Current

us-gaap:OtherLiabilitiesCurrent

us-gaap:OtherLiabilitiesCurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value7.9444.2727.1395.6294.7433.3645.5420192.9655.9265.4245.1046.6919.1859.2895.8515.3318.5558.2515.2143.8374.9034.9784.1923.8924.9753.8143.6922.4773.893.0852.3062.4181.67
Percentage of OtherLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.81.12.11.61.30.81.34.54.20.61.21.00.91.11.91.71.00.91.91.71.00.81.31.21.01.31.61.21.21.22.12.92.01.91.3

Liabilities Noncurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:LiabilitiesNoncurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-12-31
Value95121123124125127128129131132160161161161515252525341382.2942.3512.4192.4882.6152.1882.0651.9551.734
Percentage of LiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets21.832.037.035.033.231.930.728.828.428.832.330.828.626.610.49.79.18.911.68.77.60.50.60.60.60.90.70.70.61.0

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value553000.0553000.0553000.0553000.0553000.0553000.0553000.0553000.0553000.0553000.0553000.0553000.0000126000.0126000.0126000.0126000.0126000.0126000.00
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets0.10.10.20.20.10.10.10.10.10.10.10.10.00.00.00.00.00.00.00.00.00.0

Operating Lease Liability Noncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value9.4261012131516171920210.0
Percentage of OperatingLeaseLiabilityNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets2.22.93.73.94.04.14.34.24.44.70.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value6535000.06535000.06350000.06191000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0100.0100.0100.0
Percentage of Assets1.51.71.91.7

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2020-12-312020-09-30
Value6535000.06350000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0100.0
Percentage of Assets2.01.8

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2020-09-30
Value6535000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0
Percentage of Assets1.8

Operating Lease Liability

us-gaap:OperatingLeaseLiability

us-gaap:OperatingLeaseLiability


Operating
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-31
Value1516171922242526
Percentage of OperatingLeaseLiability100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.54.35.35.45.55.45.55.8

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value16171920222325262729
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.74.65.75.85.85.96.05.96.16.4

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue us-gaap:StatementGeographical

prta:DublinIreland


Lessee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.1187090.0160.0220.0280.010.0180.0250.0280.0090.015
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue0.70.10.10.10.00.10.10.10.00.1
Percentage of Assets0.00.00.00.00.00.00.00.00.00.0
Percentage of Assets prta:DublinIreland0.00.00.00.00.00.00.00.00.00.0

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value856000.01027000.01212000.01411000.0
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0100.0100.0100.0
Percentage of Assets0.20.30.40.4

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value28823418420923425527228930231232233935640940744648649636540143046536037739527728930129819317398107117126
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets66.061.855.358.961.963.965.164.165.567.964.864.763.267.582.083.084.185.379.483.685.794.893.694.796.195.895.396.295.794.795.091.590.994.897.8

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value288234184209234255272289302312322339356409407365360289173126-6.436-0.03
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets66.061.855.358.961.963.965.164.165.567.964.864.763.267.582.079.493.695.395.097.80.00.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

prta:OrdinaryShare


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value0.4490.4420.3990.3990.3990.3990.3990.3990.3990.3990.3990.3980.3980.3980.3850.3480.3170.2740.2190.1770.00.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.20.20.20.20.20.20.10.10.10.10.10.10.10.10.10.10.10.10.10.1-0.0-0.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.00.0
Percentage of Assets prta:OrdinaryShare0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value107910539669619559509449399339269209149069008496544893382141260.00.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest374.7449.3525.3458.9407.7372.5346.0324.8308.2296.9285.0269.3254.7219.8208.5179.1135.7116.6123.7100.1-0.0-0.0
Percentage of Assets247.5277.5290.3270.2252.2237.9225.3208.3202.0201.7184.6174.4160.9148.4171.1142.2127.1111.2117.598.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value-792.122-819.764-783.029-752.313-721.736-695.454-671.885-650.331-630.883-615.073-597.995-575.534-550.975-491.093-442.35-289.211-129.103-48.491-41.341-0.3450.00.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-274.8-349.5-425.5-359.1-307.9-272.7-246.2-224.9-208.3-197.1-185.1-169.4-154.8-119.9-108.6-79.1-35.8-16.7-23.9-0.3-0.0-0.0
Percentage of Assets-181.5-215.9-235.2-211.5-190.5-174.1-160.3-144.2-136.5-133.8-119.9-109.7-97.8-81.0-89.1-62.9-33.5-15.9-22.7-0.30.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value449000.0442000.0399000.0399000.0399000.0399000.0399000.0399000.0399000.0399000.0399000.0398000.0398000.0398000.0385000.0384000.0382000.0380000.0348000.0344000.0343000.0343000.0317000.0315000.0314000.0275000.0274000.0274000.0267000.0219000.0219000.0177000.0177000.0177000.0177000.0
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.20.20.10.1

Additional Paid In Capital

us-gaap:AdditionalPaidInCapital

us-gaap:AdditionalPaidInCapital


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value10791053966961955950944939933926920914906900849840828820654641627622489482476340338336320216214128127126126
Percentage of AdditionalPaidInCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets247.5277.5290.3270.2252.2237.9225.3208.3202.0201.7184.6174.4160.9148.4171.1156.3143.1141.0142.2133.7124.9126.6127.1121.0116.0117.7111.2107.4102.8106.1117.5119.4108.2102.198.0

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value-792120000.0-819760000.0-783030000.0-752310000.0-721740000.0-695450000.0-671880000.0-650330000.0-630880000.0-615070000.0-598000000.0-575530000.0-550980000.0-491090000.0-442350000.0-394590000.0-342200000.0-324500000.0-289210000.0-240310000.0-197070000.0-156620000.0-129100000.0-104950000.0-81970000.0-63693000.0-48491000.0-35381000.0-22199000.0-23489000.0-41341000.0-30287000.0-20598000.0-9296000.0-345000.0
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-181.5-215.9-235.2-211.5-190.5-174.1-160.3-144.2-136.5-133.8-119.9-109.7-97.8-81.0-89.1-73.4-59.1-55.8-62.9-50.1-39.2-31.9-33.5-26.3-19.9-22.0-15.9-11.3-7.1-11.5-22.7-28.1-17.5-7.5-0.3

Stock Issued During Period Value New Issues

us-gaap:StockIssuedDuringPeriodValueNewIssues

us-gaap:StockIssuedDuringPeriodValueNewIssues


Stock
Period End2021-03-312018-12-312018-09-302018-06-302018-03-312014-07-31
Value780.00.00.039117
Percentage of StockIssuedDuringPeriodValueNewIssues100.00.00.00.0100.0100.0
Percentage of Assets0.00.00.00.00.00.0

us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents

prta:OrdinaryShare


Stock
Period End2021-03-312018-12-312018-09-302018-06-302018-03-31
Value0.040.00.00.00.012
Percentage of StockIssuedDuringPeriodValueNewIssues0.10.00.00.00.0
Percentage of Assets0.00.00.00.00.0
Percentage of Assets prta:OrdinaryShare0.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-03-312018-12-312018-09-302018-06-302018-03-31
Value780.00.00.039
Percentage of StockIssuedDuringPeriodValueNewIssues99.90.00.00.0100.0
Percentage of Assets0.00.00.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.0

us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:StatementEquityComponents, us-gaap:SubsidiarySaleOfStock

prta:OrdinaryShare, prta:AtTheMarketOffering


Stock
Period End2021-06-30
Value0.003
Percentage of StockIssuedDuringPeriodValueNewIssues0.0
Percentage of Assets0.0
Percentage of Assets prta:OrdinaryShare prta:AtTheMarketOffering0.0

prta:OrdinaryShare, prta:UnderwrittenPublicOffering


Stock
Period End2021-03-31
Value78
Percentage of StockIssuedDuringPeriodValueNewIssues100.1
Percentage of Assets0.0
Percentage of Assets prta:OrdinaryShare prta:UnderwrittenPublicOffering0.0

us-gaap:AdditionalPaidInCapital, prta:AtTheMarketOffering


Stock
Period End2021-06-30
Value13
Percentage of StockIssuedDuringPeriodValueNewIssues0.0
Percentage of Assets0.0
Percentage of Assets us-gaap:AdditionalPaidInCapital prta:AtTheMarketOffering0.0

us-gaap:StockIssuedDuringPeriodValueNewIssues us-gaap:SubsidiarySaleOfStock

prta:AtTheMarketOffering


Stock
Period End2021-06-30
Value13
Percentage of StockIssuedDuringPeriodValueNewIssues0.0
Percentage of Assets0.0
Percentage of Assets prta:AtTheMarketOffering0.0

Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue


Adjustments
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value5.546.1765.6875.5365.2875.8166.2776.2055.8097.0426.3096.902
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value5.546.1765.6875.5365.2875.8166.2776.2055.8097.0426.3096.902
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value36-33.666-19.094-19.404-18.697-23.167-14.488-8.943-12.103-17.435-21.252-33.57358-31.584-39.524-17.738-36.079-37.842-33.998-30.588-27.53-25.153-19.681-16.914-11.14-14.72-12.523-12.2656.21117-9.836-10.304-6.855-5.103-15.635-7.449-10.364-8.624
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax61.0-21041.2-5303.9-12359.2-9588.2-16430.5-5659.4-4362.4-7247.3-9373.7-10954.6-13165.920836.2-13913.7-17259.4-8099.5-134.6-14610.8-19881.9-10695.1-8267.3-9491.7-6410.7-3942.7-4007.2-2482.3-622.1-825.441.155.5-5889.8-6025.7-4104.8-2984.2-2719.1-789.1-1410.1-2134.7

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0-48000.0-51000.0-77000.0-46000.0-22000.0-106000.0-249000.0-69000.0-123000.0-1297000.0-152000.0-99000.0-181000.0-376000.0-538000.0-208000.0-2399000.0-3091000.0-8555000.0-4760000.0-238000.0-985000.0-329000.0-40000.0-28000.0-40000.0-106000.0-327000.0-26000.03000.0-227000.0-201000.0-110000.0-1027000.0-103000.0-34000.0-137000.0
Percentage of NetCashProvidedByUsedInInvestingActivities0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-30.0-14.2-49.0-23.6-15.6-41.4-121.5-41.3-66.1-668.6-59.6-35.5-79.7-164.2-245.7-0.8-926.3-1807.6-2991.3-1429.4-89.8-320.8-76.7-14.4-4.7-2.0-7.1-2.2-0.11.8-132.7-120.4-64.3-178.6-10.9-4.6-33.9

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value20810.00.0640.00.1510.0130.00.210.005-1.304-0.975-0.861431.4592.6081.466159194.7690.9861293.452.6561331.026-0.011141020.50784-0.1170.0-0.0841417.552108.761
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.00.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax33.750829.40.040.80.0107.15.10.0125.72.7-672.2-382.4-308.619023.8637.11190.95.561725.111400.01667.5296.148700.81123.8619.148097.8173.0-0.5987.4680.61.650689.2-68.40.0-49.124612.5800.01414.72168.6

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-19.417-18.743-23.038-9.192-11.962-17.553
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-12367.5-9611.8-16339.0-4483.9-7162.9-9437.1

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value291000.0304000.0362000.0387000.0381000.0384000.0400000.0392000.0387000.0385000.0826000.0794000.0799000.0797000.0782000.0767000.0759000.0759000.0918000.0830000.0428000.0251000.0218000.0200000.0195000.0193000.0194000.0200000.0200000.0175000.0232000.0100000.0200000.0137000.0162000.078000.0115000.0113000.0
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Accounts Receivable

us-gaap:IncreaseDecreaseInAccountsReceivable

us-gaap:IncreaseDecreaseInAccountsReceivable


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.002-0.014-0.007-0.034-0.1180.1060.0-0.0070.0050.002-0.008-100.004990.02-30.02290.093-0.2310.045-0.6390.494-0.305-0.147-0.396-0.3720.762-0.524-0.672.1610.00.00.00.0
Percentage of IncreaseDecreaseInAccountsReceivable100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value36-33.666-19.094-19.404-18.697-23.167-14.488-8.943-12.103-17.435-21.252-33.57358-31.584-39.524-17.738-36.079-37.842-33.998-30.588-27.53-25.153-19.681-16.914-11.14-14.72-12.523-12.2656.21117-9.836-10.304-6.855-5.103-15.635-7.449-10.364-8.624
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax61.0-21041.2-5303.9-12359.2-9588.2-16430.5-5659.4-4362.4-7247.3-9373.7-10954.6-13165.920836.2-13913.7-17259.4-8099.5-134.6-14610.8-19881.9-10695.1-8267.3-9491.7-6410.7-3942.7-4007.2-2482.3-622.1-825.441.155.5-5889.8-6025.7-4104.8-2984.2-2719.1-789.1-1410.1-2134.7

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value27-36.735-30.716-30.577-26.282-23.569-21.554-19.448-15.81-20.865-22.461-24.559-59.882-48.743-47.758-52.394-17.701-35.384-48.903-43.239-40.445-27.521-24.157-22.976-18.277-15.202-13.11-13.1821.2917-11.054-9.689-11.302-8.951-12.221-8.668-9.711-10.811
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.0-22959.4-8532.2-19475.8-13477.9-16715.6-8419.5-9486.8-9467.1-11217.7-11577.8-9631.0-21463.1-21472.7-20855.0-23924.2-66.0-13661.8-28598.2-15118.5-12145.6-10385.3-7868.7-5355.7-6574.5-2563.6-651.3-887.18.555.4-6619.2-5666.1-6767.7-5234.5-2125.4-918.2-1321.2-2676.0

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value27-36.735-30.716-30.577-26.282-23.569-21.554-19.448-15.81-20.865-22.461-24.559-59.882-48.743
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax46.0-22959.4-8532.2-19475.8-13477.9-16715.6-8419.5-9486.8-9467.1-11217.7-11577.8-9631.0-21463.1-21472.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Share Based Compensation

us-gaap:ShareBasedCompensation

us-gaap:ShareBasedCompensation


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value5.546.1765.2085.5835.6875.5365.2875.8166.2776.2054.2457.0428.8216.9027.4077.1026.6535.6025.211114.5463.7243.2783.0172.4161.7031.3981.4181.4381.3431.0910.9550.7420.340.3650.5081.6553.57
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShareBasedCompensation us-gaap:IncomeStatementLocation

us-gaap:GeneralAndAdministrativeExpense


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value3.3234.2223.1573.4953.6293.5193.3323.8614.1774.1063.6784.1543.7564.6444.3564.2823.9183.2943.3449.4582.7282.3051.931.7971.4470.9450.7780.8170.8720.860.7270.6440.5160.261
Percentage of ShareBasedCompensation60.068.460.662.663.863.663.066.466.566.286.659.042.667.358.860.358.958.864.282.660.061.958.959.659.955.555.757.660.664.066.667.469.576.8

us-gaap:ResearchAndDevelopmentExpense


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value2.2171.9542.0512.0882.0582.0171.9551.9552.12.0992.1312.8882.5532.2583.0512.822.7352.3081.8671.991.8181.4191.3481.220.9690.7580.620.6010.5660.4830.3640.3110.2260.079
Percentage of ShareBasedCompensation40.031.639.437.436.236.437.033.633.533.850.241.028.932.741.239.741.141.235.817.440.038.141.140.440.144.544.342.439.436.033.432.630.523.2

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0-48000.0-51000.0-77000.0-46000.0-22000.0-106000.0-249000.0-69000.0-123000.0-1297000.0-152000.0-99000.0-181000.0-376000.0-538000.0-208000.0-2399000.0-3091000.0-8555000.0-4760000.0-238000.0-985000.0-329000.0-40000.0-28000.0-40000.0-106000.0-327000.0-26000.03000.0-227000.0-201000.0-110000.0-1027000.0-103000.0-34000.0-137000.0
Percentage of NetCashProvidedByUsedInInvestingActivities0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-30.0-14.2-49.0-23.6-15.6-41.4-121.5-41.3-66.1-668.6-59.6-35.5-79.7-164.2-245.7-0.8-926.3-1807.6-2991.3-1429.4-89.8-320.8-76.7-14.4-4.7-2.0-7.1-2.2-0.11.8-132.7-120.4-64.3-178.6-10.9-4.6-33.9

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value20810.00.0640.00.1510.0130.00.210.005-1.304-0.975-0.861431.4592.6081.466159194.7690.9861293.452.6561331.026-0.011141020.50784-0.1170.0-0.0841417.552108.761
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.00.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax33.750829.40.040.80.0107.15.10.0125.72.7-672.2-382.4-308.619023.8637.11190.95.561725.111400.01667.5296.148700.81123.8619.148097.8173.0-0.5987.4680.61.650689.2-68.40.0-49.124612.5800.01414.72168.6

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber


Share
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value8814100.08825500.08744800.08672200.08412400.07008400.07185000.07168500.07253000.06726700.07252600.07719400.04406800.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value16.8916.2320.4220.9721.0921.4123.3423.4424.4124.6926.8227.8728.7338.93
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice us-gaap:PlanName

prta:A2018LongTermIncentivePlan


Share
Period End2020-11-09
Value17.63
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice0.0

Deferred Tax Assets Net

us-gaap:DeferredTaxAssetsNet

us-gaap:DeferredTaxAssetsNet


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value1615108.7185.9132.851.8870.8970.079
Percentage of DeferredTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits

us-gaap:UnrecognizedTaxBenefits


Unrecognized
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value7252000.06601000.06855000.04268000.02406000.01061000.0383000.0480000.00
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.00.0

Deferred Tax Assets Valuation Allowance

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:DeferredTaxAssetsValuationAllowance


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value13712111183563118178.917
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.0100.0100.0100.0100.0

prta:Amortizationofrightofuseasset

prta:Amortizationofrightofuseasset


Amortizationofrightofuseasset
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1415000.01400000.01386000.01373000.01359000.01345000.01333000.01320000.01307000.01296000.00000
Percentage of Amortizationofrightofuseasset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

prta:CollaborationAgreementExerciseFeeUSRightsPerProgram us-gaap:CounterpartyName, us-gaap:ProductOrService, us-gaap:SubsequentEventType

prta:CollaborationAgreementExerciseFeeUSRightsPerProgram

prta:BristolMyersSquibb, prta:CollaborationProgramUSRights, us-gaap:SubsequentEvent


Collaboration
Period End2021-07-30
Value80
Percentage of CollaborationAgreementExerciseFeeUSRightsPerProgram100.0

prta:CollaborationAgreementPotentialRegulatoryandCommercialMilestonePaymentsPerProgram us-gaap:CounterpartyName, us-gaap:ProductOrService, us-gaap:SubsequentEventType

prta:CollaborationAgreementPotentialRegulatoryandCommercialMilestonePaymentsPerProgram

prta:BristolMyersSquibb, prta:CollaborationProgramUSRights, us-gaap:SubsequentEvent


Collaboration
Period End2021-07-30
Value465
Percentage of CollaborationAgreementPotentialRegulatoryandCommercialMilestonePaymentsPerProgram100.0

prta:CollaborationRevenue

prta:CollaborationRevenue


Collaboration
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.20.10.1410.2560.2050.1670.1860.1940.2550.2790.2270.2290.219260.2590.1710.2860.3330.2650.3070.4290.2780.5931.8911.34914320.00.00.00.0
Percentage of CollaborationRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

prta:DeferredTaxAssetsPeriodIncreaseDecrease

prta:DeferredTaxAssetsPeriodIncreaseDecrease


Deferred
Period End2021-06-302021-03-31
Value600000.04600000.0
Percentage of DeferredTaxAssetsPeriodIncreaseDecrease100.0100.0

prta:DeferredTaxAssetsPeriodIncreaseDecreaseTaxCutsAndJobsAct

prta:DeferredTaxAssetsPeriodIncreaseDecreaseTaxCutsAndJobsAct


Deferred
Period End2021-06-302021-03-31
Value03500000.0
Percentage of DeferredTaxAssetsPeriodIncreaseDecreaseTaxCutsAndJobsAct0.0100.0

prta:IncreaseDecreaseinOperatingLeaseLiability

prta:IncreaseDecreaseinOperatingLeaseLiability


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1352000.01337000.01323000.01293000.01249000.01236000.01224000.01195000.01155000.01143000.00000
Percentage of IncreaseDecreaseinOperatingLeaseLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

prta:LicenseAgreementPotentialAlternativeCommercialSalesMilestones us-gaap:CounterpartyName, us-gaap:TypeOfArrangement

prta:LicenseAgreementPotentialAlternativeCommercialSalesMilestones

prta:Roche, us-gaap:CollaborativeArrangement


License
Period End2021-06-302021-03-312020-12-31
Value0.01550.0
Percentage of LicenseAgreementPotentialAlternativeCommercialSalesMilestones0.0100.00.0

prta:LicenseAgreementPotentialPaymentUponAchievementofDevelopmentRegulatoryandVariousFirstCommercialSalesMilestones us-gaap:CounterpartyName, us-gaap:TypeOfArrangement

prta:LicenseAgreementPotentialPaymentUponAchievementofDevelopmentRegulatoryandVariousFirstCommercialSalesMilestones

prta:Roche, us-gaap:CollaborativeArrangement


License
Period End2021-06-302021-03-312020-12-31
Value-60.03500.0
Percentage of LicenseAgreementPotentialPaymentUponAchievementofDevelopmentRegulatoryandVariousFirstCommercialSalesMilestones100.0100.00.0

prta:LicenseAgreementPotentialPaymentforAchievementofnonU.S.CommercialSalesMilestones us-gaap:CounterpartyName, us-gaap:TypeOfArrangement

prta:LicenseAgreementPotentialPaymentforAchievementofnonU.S.CommercialSalesMilestones

prta:Roche, us-gaap:CollaborativeArrangement


License
Period End2021-06-302021-03-312020-12-31
Value0.01750.0
Percentage of LicenseAgreementPotentialPaymentforAchievementofnonU.S.CommercialSalesMilestones0.0100.00.0

prta:LicensingAgreementCostAllocationPercentage us-gaap:CounterpartyName, us-gaap:TypeOfArrangement

prta:LicensingAgreementCostAllocationPercentage

prta:Roche, us-gaap:CollaborativeArrangement


Licensing
Period End2021-06-302021-03-312020-12-31
Value0100.00
Percentage of LicensingAgreementCostAllocationPercentage0.0100.00.0

prta:LicensingAgreementPortionofRevenueandExpensesAttributabletoCompanyPercentage us-gaap:CounterpartyName, us-gaap:TypeOfArrangement

prta:LicensingAgreementPortionofRevenueandExpensesAttributabletoCompanyPercentage

prta:Roche, us-gaap:CollaborativeArrangement


Licensing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312014-12-312014-09-302014-06-302014-03-31
Value070.0069.300.70000.70000.70000.7
Percentage of LicensingAgreementPortionofRevenueandExpensesAttributabletoCompanyPercentage0.0100.00.0100.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.0

prta:LicensingAgreementPortionofRevenueandExpensesAttributabletoCompanyPercentage us-gaap:TypeOfArrangement

us-gaap:CollaborativeArrangement


Licensing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312014-12-312014-09-302014-06-302014-03-31
Value030.0029.700.30000.30000.30000.3
Percentage of LicensingAgreementPortionofRevenueandExpensesAttributabletoCompanyPercentage0.042.90.042.90.042.90.00.00.042.90.00.00.042.90.00.00.042.9

prta:MilestoneAchievementClinicalMilestone us-gaap:CounterpartyName, us-gaap:SubsequentEventType

prta:MilestoneAchievementClinicalMilestone

prta:Roche, us-gaap:SubsequentEvent


Milestone
Period End2021-05-05
Value60
Percentage of MilestoneAchievementClinicalMilestone100.0

prta:OfferingCostsIncludedInAccountsPayableAndAccruedLiabilities

prta:OfferingCostsIncludedInAccountsPayableAndAccruedLiabilities


Offering
Period End2021-03-31
Value313000.0
Percentage of OfferingCostsIncludedInAccountsPayableAndAccruedLiabilities100.0

prta:PotentialWithholdingTaxRate us-gaap:IncomeTaxAuthorityName

prta:PotentialWithholdingTaxRate

us-gaap:InternalRevenueServiceIRS


Potential
Period End2021-06-302021-03-312019-09-302019-06-302019-03-31
Value05.0000.05
Percentage of PotentialWithholdingTaxRate0.0100.00.00.0100.0

prta:ReceivableFromOptionsExercises

prta:ReceivableFromOptionsExercises


Receivable
Period End2021-06-302021-03-31
Value-115000.0123000.0
Percentage of ReceivableFromOptionsExercises100.0100.0

prta:ResearchAndDevelopmentPaymentToCollaborationPartnerRecordedAsResearchAndDevelopmentExpense us-gaap:CounterpartyName, us-gaap:TypeOfArrangement

prta:ResearchAndDevelopmentPaymentToCollaborationPartnerRecordedAsResearchAndDevelopmentExpense

prta:Roche, us-gaap:CollaborativeArrangement


Research
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value2.84.45.13.84.53.94.72.71.12.83.53.14.02.41.51.62.91.30.71.00.90.50.70.80.80.50.40.50.40.2
Percentage of ResearchAndDevelopmentPaymentToCollaborationPartnerRecordedAsResearchAndDevelopmentExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

prta:SharebasedCompensationNetTaxShortfallExcessTaxBenefitAmountBookedtoIncomeTaxProvision

prta:SharebasedCompensationNetTaxShortfallExcessTaxBenefitAmountBookedtoIncomeTaxProvision


Sharebased
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value900000.000100000.0700000.0900000.0300000.0700000.0400000.0958000.016000.0300000.0100000.0-2000000.0-1500000.0-1900000.0
Percentage of SharebasedCompensationNetTaxShortfallExcessTaxBenefitAmountBookedtoIncomeTaxProvision100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

prta:SharebasedCompensationnonrestructuring

prta:SharebasedCompensationnonrestructuring


Sharebased
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value5.546.1765.6875.5365.2875.8166.2776.2055.8097.0426.3096.9027.4077.102
Percentage of SharebasedCompensationnonrestructuring100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

prta:StockIssuanceCosts us-gaap:SubsidiarySaleOfStock

prta:StockIssuanceCosts

prta:AtTheMarketOffering


Stock
Period End2021-06-30
Value-500000.0
Percentage of StockIssuanceCosts100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition

us-gaap:AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition


Adjustments
Period End2020-09-302020-06-302019-09-302019-06-30
Value5.5835.6875.8166.277
Percentage of AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition100.0100.0100.0100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2020-09-302020-06-302019-09-302019-06-30
Value5.5835.6875.8166.277
Percentage of AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition100.0100.0100.0100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts

us-gaap:AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts


Adjustments
Period End2021-06-30
Value5000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts us-gaap:StatementEquityComponents, us-gaap:SubsidiarySaleOfStock

us-gaap:AdditionalPaidInCapital, prta:PublicOffering


Adjustments
Period End2021-06-30
Value5000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts100.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-06-302020-03-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value5647-18.743-23.038-11.962-17.553-23.853-34.75711-38.441-15.668-34.821119-21.651-34.374
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxesAndTaxCredits

us-gaap:DeferredIncomeTaxesAndTaxCredits


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value591000.04622000.0-120000.0-507000.0-566000.0-495000.0-497000.033000.0-589000.0-195000.0-2839000.02448000.0-1593000.0395000.0-1721000.0-636000.0-580000.0737000.0-92000.0-2302000.0-409000.0-445000.0-259000.0-278000.0-57000.0-369000.0-302000.0-205000.0-324000.0-159000.048000.0-180000.0-406000.00
Percentage of DeferredIncomeTaxesAndTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:Depreciation

us-gaap:Depreciation


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value300000.0300000.0300000.0400000.0400000.0400000.0400000.0400000.0400000.0400000.0800000.0800000.0800000.0800000.0800000.0800000.0800000.0800000.0900000.0800000.0400000.0300000.0200000.0200000.0200000.0200000.0200000.0200000.0200000.0200000.0300000.0100000.0200000.0100000.0200000.0100000.0100000.0100000.0
Percentage of Depreciation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate us-gaap:IncomeTaxAuthorityName

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate

us-gaap:RevenueCommissionersIreland


Effective
Period End2021-06-302021-03-312020-12-312020-09-302018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-31
Value012.5012.3750000.1250000.1250000.1250000.125000.125
Percentage of EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate0.0100.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.0100.0

us-gaap:EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense us-gaap:AwardType

us-gaap:EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense

us-gaap:CommonStock


Employee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1100000.01200000.01000000.01100000.01100000.01100000.01100000.01200000.01200000.01200000.01300000.01300000.01000000.01100000.01200000.01100000.01100000.0900000.0800000.02100000.0700000.0600000.0
Percentage of EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value4.638-2.8514.0593.081.337-0.748-14.0713.57913-2.598-2.283-11.123-9.487-2.735-3.077-1.0877.142-2.8314.1891.6558.740.6093.6595.5944.129-2.2212.236-0.9822.4311.7460.499-1.7363.793.68-3.2740.65-2.449-1.464
Percentage of IncreaseDecreaseInAccountsPayableAndAccruedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingAssets

us-gaap:IncreaseDecreaseInOtherOperatingAssets


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value2.1445.259-2.043-2.516-0.5184.278-15.84-0.56150.054-3.727-2.421-2.569-0.422-3.9342.4393.2925.452-4.327-1.3671.151.1811.2411.256-0.627-0.9332.24-0.026-0.5690.7070.648-0.2010.0030.2710.4440.017-0.0260.032
Percentage of IncreaseDecreaseInOtherOperatingAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

us-gaap:IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends


Incremental
Period End2021-06-30
Value3082000.0
Percentage of IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends100.0

us-gaap:NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1

us-gaap:NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1


Noncash
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-06-302014-03-312013-03-31
Value-6000.019000.024000.0-77000.070000.04000.08000.0-105000.0195000.0-79000.079000.012000.0-230000.0305000.088000.0-3502000.04061000.0-244000.0260000.0185000.0-15000.015000.00-10000.010000.00
Percentage of NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0

us-gaap:OperatingLeaseCost

us-gaap:OperatingLeaseCost


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1600000.01600000.01500000.01600000.01600000.01600000.01600000.01600000.01600000.01600000.0
Percentage of OperatingLeaseCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingLeasePayments

us-gaap:OperatingLeasePayments


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1500000.01500000.01500000.01500000.01500000.01500000.01500000.01500000.01400000.01400000.0
Percentage of OperatingLeasePayments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsOfStockIssuanceCosts

us-gaap:PaymentsOfStockIssuanceCosts


Payments
Period End2021-03-312015-03-312014-03-312013-03-31
Value5500000.0010000.00
Percentage of PaymentsOfStockIssuanceCosts100.00.0100.00.0

us-gaap:PaymentsToAcquireBusinessesGross dei:LegalEntity, us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType

us-gaap:PaymentsToAcquireBusinessesGross

prta:Novo, prta:ProthenaBiosciencesLimited, us-gaap:SubsequentEvent


Payments
Period End2021-07-08
Value60
Percentage of PaymentsToAcquireBusinessesGross100.0

us-gaap:PaymentsToAcquireMachineryAndEquipment

us-gaap:PaymentsToAcquireMachineryAndEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value0.00.0480.0510.0770.0460.0220.1060.2490.0690.1311.3360.1520.0990.1810.3760.5380.2132.4997.1478.5550.7040.2380.9850.3290.040.0280.0670.1060.3270.026-0.0030.2270.230.111.0270.103
Percentage of PaymentsToAcquireMachineryAndEquipment0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromIssuanceOfCommonStock

us-gaap:ProceedsFromIssuanceOfCommonStock


Proceeds
Period End2021-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-312013-09-30
Value780.00.00.00.00.00.0-0.0981500.00.0-0.008128-0.140.01310.0-0.04314840.0
Percentage of ProceedsFromIssuanceOfCommonStock100.00.00.00.00.00.00.0100.0100.00.00.0100.0100.0100.00.0100.00.0100.0100.0100.00.0

us-gaap:ProceedsFromStockOptionsExercised

us-gaap:ProceedsFromStockOptionsExercised


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value6.5942.960.00.0640.00.1510.0130.00.210.0050.00.2130.0934.382.4143.4112.0659.9488.121.430.790.1762.0861.2941.6320.6360.0520.0520.080.310.00.00.00.0
Percentage of ProceedsFromStockOptionsExercised100.0100.00.0100.00.0100.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value81.781.3-0.279.60.7960.81500.810.8150.8150.00100.8390.672-0.0020.7120.722
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value1.11.0-0.10.30.0040.01200.0180.0220.025000.0280.02800.020.02
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate100.0100.0100.0100.0100.0100.00.0100.0100.0100.00.00.0100.0100.00.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue

us-gaap:CommonStock


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value112.50.0060.0590.00.0350.00.00.10.00610.00.30.12.10.4138.9178.72.71.10.3127.03.62.20.00.10.11.3
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue100.0100.0100.0100.00.0100.00.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross


Share
Period End2021-02-12
Value1400000.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value17.5815.09-0.18.567.528.32-0.067.096.589.48-0.12011.2820.670.0838.0635.37
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-31
Value1.1813.430
Percentage of ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice100.0100.00.0

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-31
Value040.98-3.48
Percentage of ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice0.0100.0100.0

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-31
Value-6.1230.61.47
Percentage of ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice


Share
Period End2021-06-302021-02-122021-03-312020-12-31
Value0.5622.8522.39-0.13
Percentage of ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodSharesNewIssues us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesNewIssues

prta:OrdinaryShare


Stock
Period End2021-03-31
Value4.025
Percentage of StockIssuedDuringPeriodSharesNewIssues100.0

us-gaap:StockIssuedDuringPeriodSharesNewIssues us-gaap:StatementEquityComponents, us-gaap:SubsidiarySaleOfStock

prta:OrdinaryShare, prta:AtTheMarketOffering


Stock
Period End2021-06-30
Value0.311996
Percentage of StockIssuedDuringPeriodSharesNewIssues0.0

prta:OrdinaryShare, prta:UnderwrittenPublicOffering


Stock
Period End2021-03-31
Value4.025
Percentage of StockIssuedDuringPeriodSharesNewIssues100.0

us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised

prta:OrdinaryShare


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value425240.0229380.0010000.0012852.02000.0032000.0850.0031875.010037.0164500.0
Percentage of StockIssuedDuringPeriodSharesStockOptionsExercised100.0100.00.0100.00.0100.0100.00.0100.0100.00.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised

us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value6.4793.0830.00.0640.00.1510.0130.00.210.0050.00.2130.0744.399
Percentage of StockIssuedDuringPeriodValueStockOptionsExercised100.0100.00.0100.00.0100.0100.00.0100.0100.00.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised us-gaap:StatementEquityComponents

prta:OrdinaryShare


Stock
Period End2021-06-302021-03-312018-12-312018-09-302018-06-302018-03-31
Value0.0040.0030.0010.00.00.001
Percentage of StockIssuedDuringPeriodValueStockOptionsExercised0.10.10.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value6.4753.080.00.0640.00.1510.0130.00.210.005-0.0010.2130.0744.398
Percentage of StockIssuedDuringPeriodValueStockOptionsExercised99.999.90.0100.00.0100.0100.00.0100.0100.00.0100.0100.0100.0

dei:EntityCommonStockSharesOutstanding

dei:EntityCommonStockSharesOutstanding


Entity
Period End2020-10-30
Value39
Percentage of EntityCommonStockSharesOutstanding100.0

prta:ASC605AllocatedConsiderationToDeliverables us-gaap:CounterpartyName, us-gaap:ProductOrService

prta:ASC605AllocatedConsiderationToDeliverables

prta:Roche, prta:ClinicalProductSupply


A
Period End2020-12-31
Value0.8
Percentage of ASC605AllocatedConsiderationToDeliverables100.0

prta:Roche, prta:INDandDevelopmentServices


A
Period End2020-12-31
Value3.3
Percentage of ASC605AllocatedConsiderationToDeliverables412.5

prta:Roche, prta:RoyaltyBearingLicense


A
Period End2020-12-31
Value35
Percentage of ASC605AllocatedConsiderationToDeliverables4450.0

prta:Roche, prta:SupplyServices


A
Period End2020-12-31
Value0.4
Percentage of ASC605AllocatedConsiderationToDeliverables50.0

prta:AccruedResearchAndDevelopmentCurrent

prta:AccruedResearchAndDevelopmentCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value8.3759.3559.0447.6176.1525.2235.8264.2532.264.7385.375.9510151318202119161610129.5226.3993.6622.2854.6355.734.3591.5423.1175.6982.5960.047
Percentage of AccruedResearchAndDevelopmentCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

prta:DeferredSharesSharesAuthorized

prta:DeferredSharesSharesAuthorized


Deferred
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value10000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000.010000000.010000000.010000000.0
Percentage of DeferredSharesSharesAuthorized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

prta:DeferredTaxAssetPeriodIncreaseDecreaseAmericanRescuePlanAct

prta:DeferredTaxAssetPeriodIncreaseDecreaseAmericanRescuePlanAct


Deferred
Period End2021-03-31
Value900000.0
Percentage of DeferredTaxAssetPeriodIncreaseDecreaseAmericanRescuePlanAct100.0

prta:DeferredTaxAssetsLeaseLiabilities

prta:DeferredTaxAssetsLeaseLiabilities


Deferred
Period End2020-12-312019-12-312018-12-31
Value4199000.05319000.00
Percentage of DeferredTaxAssetsLeaseLiabilities100.0100.00.0

prta:DeferredTaxLiabilitiesOperatingLeaseRightofUseAssets

prta:DeferredTaxLiabilitiesOperatingLeaseRightofUseAssets


Deferred
Period End2020-12-312019-12-312018-12-31
Value4192000.05397000.00
Percentage of DeferredTaxLiabilitiesOperatingLeaseRightofUseAssets100.0100.00.0

prta:LesseeOperatingLeaseLiabilityNominalPayments

prta:LesseeOperatingLeaseLiabilityNominalPayments


Lessee
Period End2021-06-302021-03-312020-12-312020-09-30
Value141000.019000.027000.033000.0
Percentage of LesseeOperatingLeaseLiabilityNominalPayments100.0100.0100.0100.0

prta:NearTermClinicalMilestone us-gaap:CounterpartyName, us-gaap:SubsequentEventType

prta:NearTermClinicalMilestone

prta:Novo, us-gaap:SubsequentEvent


Near
Period End2021-07-08
Value40
Percentage of NearTermClinicalMilestone100.0

prta:NumberOfOrdinarySharesTenderedForExchangeUnderTheOptionExchage

prta:NumberOfOrdinarySharesTenderedForExchangeUnderTheOptionExchage


Number
Period End2021-02-12
Value2100000.0
Percentage of NumberOfOrdinarySharesTenderedForExchangeUnderTheOptionExchage100.0

prta:PurchaseandContractualObligationDueAfterFifthYear

prta:PurchaseandContractualObligationDueAfterFifthYear


Purchaseand
Period End2020-12-312020-09-30
Value345000.0405000.0
Percentage of PurchaseandContractualObligationDueAfterFifthYear100.0100.0

prta:PurchaseandContractualObligationDueNextFiscalYear

prta:PurchaseandContractualObligationDueNextFiscalYear


Purchaseand
Period End2020-12-31
Value11
Percentage of PurchaseandContractualObligationDueNextFiscalYear100.0

prta:PurchaseandContractualObligationDueinFourthYear

prta:PurchaseandContractualObligationDueinFourthYear


Purchaseand
Period End2021-06-302021-03-312020-12-312020-09-30
Value60000.060000.060000.070000.0
Percentage of PurchaseandContractualObligationDueinFourthYear100.0100.0100.0100.0

prta:PurchaseandContractualObligationDueinSecondYear

prta:PurchaseandContractualObligationDueinSecondYear


Purchaseand
Period End2021-06-302021-03-312020-12-312020-09-30
Value70000.070000.070000.085000.0
Percentage of PurchaseandContractualObligationDueinSecondYear100.0100.0100.0100.0

prta:PurchaseandContractualObligationDueinThirdYear

prta:PurchaseandContractualObligationDueinThirdYear


Purchaseand
Period End2021-06-302021-03-312020-12-312020-09-30
Value60000.060000.070000.070000.0
Percentage of PurchaseandContractualObligationDueinThirdYear100.0100.0100.0100.0

prta:PurchaseandContractualObligationRemainderofFiscalYear

prta:PurchaseandContractualObligationRemainderofFiscalYear


Purchaseand
Period End2021-06-302021-03-312020-09-30
Value12129.28
Percentage of PurchaseandContractualObligationRemainderofFiscalYear100.0100.0100.0

prta:PurchaseandContractualObligationTotal

prta:PurchaseandContractualObligationTotal


Purchaseand
Period End2021-06-302021-03-312020-12-312020-09-30
Value1212119.97
Percentage of PurchaseandContractualObligationTotal100.0100.0100.0100.0

prta:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueRelatedToVestedOptions

prta:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueRelatedToVestedOptions


Share
Period End2021-06-302021-03-312020-12-312020-09-30
Value125373.4441.918
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueRelatedToVestedOptions100.0100.0100.0100.0

us-gaap:AccruedProfessionalFeesCurrent

us-gaap:AccruedProfessionalFeesCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value1034000.0510000.0696000.0547000.0715000.0372000.0400000.0353000.0272000.0399000.01097000.0833000.0641000.0654000.0438000.0384000.0351000.0411000.0435000.0819000.0615000.0934000.0325000.0442000.0469000.0390000.01169000.0984000.01043000.0688000.0616000.0384000.0591000.01221000.027000.0
Percentage of AccruedProfessionalFeesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh dei:LegalEntity, us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType

us-gaap:BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh

prta:Novo, prta:ProthenaBiosciencesLimited, us-gaap:SubsequentEvent


Business
Period End2021-07-08
Value1170
Percentage of BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh100.0

us-gaap:CapitalizedComputerSoftwareGross

us-gaap:CapitalizedComputerSoftwareGross


Capitalized
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value1424000.01424000.01423000.01444000.01392000.01327000.01308000.01303000.01303000.01303000.01303000.01350000.01299000.01395000.01316000.0987000.0714000.0531000.0363000.0313000.0225000.0167000.0167000.0159000.0138000.0138000.0137000.0120000.0120000.0110000.085000.085000.085000.085000.0
Percentage of CapitalizedComputerSoftwareGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligation

us-gaap:ContractualObligation


Contractual
Period End2021-06-302021-03-312020-12-312016-03-312015-12-312015-09-302014-12-312014-09-302014-06-302014-03-312013-12-31
Value0.70.70.81.441.5071.6021.451.2251.2351.0491.07
Percentage of ContractualObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligation us-gaap:BalanceSheetLocation

us-gaap:LicensingAgreements


Contractual
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-312014-09-302014-06-302014-03-312013-12-31
Value0.81.11.01.01.21.21.21.31.31.61.71.61.81.71.61.51.61.41.41.51.6021.451.2251.2351.01.07
Percentage of ContractualObligation0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.097.299.5100.0100.0100.0100.095.3100.0

us-gaap:ContractualObligation us-gaap:OtherCommitments

prta:LicenseAgreements


Contractual
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value0.730.740.7850.8151.0750.9550.971.161.171.161.31.3251.5951.7251.561.7951.7251.6051.531.591.39
Percentage of ContractualObligation104.3105.798.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ContractualObligationDueAfterFifthYear us-gaap:OtherCommitments

us-gaap:ContractualObligationDueAfterFifthYear

prta:LicenseAgreements


Contractual
Period End2020-12-312020-09-302019-09-302019-06-302018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value0.3450.4050.5350.5350.6050.8450.7750.7750.860.860.860.860.960.8
Percentage of ContractualObligationDueAfterFifthYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligationDueInFifthYear us-gaap:OtherCommitments

us-gaap:ContractualObligationDueInFifthYear

prta:LicenseAgreements


Contractual
Period End2020-12-312020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value60000.060000.070000.080000.080000.080000.080000.070000.090000.085000.085000.0100000.0100000.0100000.0100000.0100000.090000.0
Percentage of ContractualObligationDueInFifthYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligationDueInFourthYear us-gaap:OtherCommitments

us-gaap:ContractualObligationDueInFourthYear

prta:LicenseAgreements


Contractual
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value60000.060000.060000.070000.080000.080000.080000.080000.080000.085000.0105000.0100000.0100000.0100000.0100000.0100000.0100000.0130000.0120000.0
Percentage of ContractualObligationDueInFourthYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligationDueInNextTwelveMonths us-gaap:OtherCommitments

us-gaap:ContractualObligationDueInNextTwelveMonths

prta:LicenseAgreements


Contractual
Period End2021-06-302021-03-312020-12-312019-12-312018-12-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value70000.070000.0180000.0180000.0415000.0370000.0475000.0405000.0285000.0210000.0
Percentage of ContractualObligationDueInNextTwelveMonths100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligationDueInSecondYear us-gaap:OtherCommitments

us-gaap:ContractualObligationDueInSecondYear

prta:LicenseAgreements


Contractual
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value70000.070000.070000.085000.095000.0105000.0105000.095000.095000.0185000.0235000.0230000.0130000.0130000.0130000.0130000.0130000.0130000.0120000.0
Percentage of ContractualObligationDueInSecondYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligationDueInThirdYear us-gaap:OtherCommitments

us-gaap:ContractualObligationDueInThirdYear

prta:LicenseAgreements


Contractual
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value60000.060000.070000.070000.080000.095000.095000.095000.095000.085000.0105000.0100000.0100000.0130000.0130000.0130000.0130000.0130000.0120000.0
Percentage of ContractualObligationDueInThirdYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractualObligationFutureMinimumPaymentsDueRemainderOfFiscalYear us-gaap:OtherCommitments

us-gaap:ContractualObligationFutureMinimumPaymentsDueRemainderOfFiscalYear

prta:LicenseAgreements


Contractual
Period End2021-06-302021-03-312020-09-302019-09-302019-06-302018-09-302018-06-302018-03-312016-09-302016-06-30
Value0.1250.1350.1250.2650.2750.2950.2150.4350.140.14
Percentage of ContractualObligationFutureMinimumPaymentsDueRemainderOfFiscalYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxAssetsNet

us-gaap:DeferredIncomeTaxAssetsNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value6.4317.022111111109.956
Percentage of DeferredIncomeTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredRevenueCurrent

us-gaap:DeferredRevenueCurrent


Deferred
Period End2021-06-30
Value24
Percentage of DeferredRevenueCurrent100.0

us-gaap:DeferredRevenueNoncurrent

us-gaap:DeferredRevenueNoncurrent


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value851101101101101101101101101101101101101100.0
Percentage of DeferredRevenueNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsGross


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value15313712192623420188.996
Percentage of DeferredTaxAssetsGross100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value1181018867472616158.917
Percentage of DeferredTaxAssetsOperatingLossCarryforwards100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsTaxCreditCarryforwardsResearch

us-gaap:DeferredTaxAssetsTaxCreditCarryforwardsResearch


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value141622164.9372.4731.1391.310.0
Percentage of DeferredTaxAssetsTaxCreditCarryforwardsResearch100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:DeferredTaxAssetsTaxCreditCarryforwardsResearch us-gaap:IncomeTaxAuthority

us-gaap:CaliforniaFranchiseTaxBoard


Deferred
Period End2020-12-312019-12-312018-12-312017-12-31
Value1211108.8
Percentage of DeferredTaxAssetsTaxCreditCarryforwardsResearch82.466.947.054.0

us-gaap:InternalRevenueServiceIRS


Deferred
Period End2020-12-312019-12-312018-12-312017-12-31
Value9.8121811
Percentage of DeferredTaxAssetsTaxCreditCarryforwardsResearch66.273.083.772.4

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value13119.3227.4448.9663.7692.2250.7790.0
Percentage of DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value2936000.02501000.01521000.01285000.01174000.01117000.01016000.01149000.079000.0
Percentage of DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value318000.0351000.0677000.0605000.0148000.0
Percentage of DeferredTaxLiabilitiesPropertyPlantAndEquipment100.0100.0100.0100.0100.0

us-gaap:EmployeeRelatedLiabilitiesCurrent

us-gaap:EmployeeRelatedLiabilitiesCurrent


Employee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value6367000.03516000.05927000.04467000.03355000.02434000.04818000.03647000.02882000.02182000.04507000.04016000.03914000.04475000.07342000.07509000.04234000.03835000.06629000.05615000.03035000.02083000.03774000.03500000.02748000.02784000.03138000.02315000.01787000.01266000.02800000.01716000.01185000.0822000.01592000.0
Percentage of EmployeeRelatedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions


Employee
Period End2021-06-302021-03-312020-12-312020-09-30
Value48443236
Percentage of EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions100.0100.0100.0100.0

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths


Lessee
Period End2021-06-302021-03-312020-12-31
Value6425000.06350000.06192000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths100.0100.0100.0

us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear

us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear


Lessee
Period End2021-06-302021-03-312020-09-30
Value3187000.04662000.01529000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear100.0100.0100.0

us-gaap:LessorOperatingLeasePaymentsToBeReceived

us-gaap:LessorOperatingLeasePaymentsToBeReceived


Lessor
Period End2021-06-302021-03-312020-12-312020-09-30
Value7555000.08282000.09010000.09737000.0
Percentage of LessorOperatingLeasePaymentsToBeReceived100.0100.0100.0100.0

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFourYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFourYears


Lessor
Period End2020-09-30
Value3019000.0
Percentage of LessorOperatingLeasePaymentsToBeReceivedFourYears100.0

us-gaap:LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths

us-gaap:LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths


Lessor
Period End2021-06-302021-03-312020-12-31
Value3047000.03047000.02944000.0
Percentage of LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths100.0100.0100.0

us-gaap:LessorOperatingLeasePaymentsToBeReceivedRemainderOfFiscalYear

us-gaap:LessorOperatingLeasePaymentsToBeReceivedRemainderOfFiscalYear


Lessor
Period End2021-06-302021-03-312020-09-30
Value1489000.02216000.0727000.0
Percentage of LessorOperatingLeasePaymentsToBeReceivedRemainderOfFiscalYear100.0100.0100.0

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThreeYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThreeYears


Lessor
Period End2020-12-312020-09-30
Value3019000.03047000.0
Percentage of LessorOperatingLeasePaymentsToBeReceivedThreeYears100.0100.0

us-gaap:LessorOperatingLeasePaymentsToBeReceivedTwoYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedTwoYears


Lessor
Period End2021-06-302021-03-312020-12-312020-09-30
Value3019000.03019000.03047000.02944000.0
Percentage of LessorOperatingLeasePaymentsToBeReceivedTwoYears100.0100.0100.0100.0

us-gaap:MoneyMarketFundsAtCarryingValue us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:MoneyMarketFundsAtCarryingValue

us-gaap:FairValueInputsLevel1


Money
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value3152732262542873123383593753853063383613363193643854283073614004253203483682482622752741731537891103
Percentage of MoneyMarketFundsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingLossCarryforwards prta:TypeofLossCarryovers, us-gaap:IncomeTaxAuthority

us-gaap:OperatingLossCarryforwards

prta:NonTradingLossCarryoverMemberDomain, us-gaap:RevenueCommissionersIreland


Operating
Period End2020-12-312019-12-312018-12-312017-12-31
Value19121110
Percentage of OperatingLossCarryforwards100.0100.0100.0100.0

prta:TradingLossCarryover, us-gaap:RevenueCommissionersIreland


Operating
Period End2020-12-312019-12-312018-12-312017-12-31
Value852748652497
Percentage of OperatingLossCarryforwards4415.06235.05621.64651.4

us-gaap:OperatingLossCarryforwards us-gaap:IncomeTaxAuthority

us-gaap:CaliforniaFranchiseTaxBoard


Operating
Period End2020-12-312019-12-31
Value8660
Percentage of OperatingLossCarryforwards447.2507.5

us-gaap:OtherSundryLiabilitiesCurrent

us-gaap:OtherSundryLiabilitiesCurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value543000.0246000.0516000.0615000.0673000.0558000.0322000.0328000.0401000.0384000.0278000.0526000.0500000.01513000.01356000.01347000.01217000.01036000.01128000.01481000.01244000.0516000.0520000.0768000.0721000.0537000.0496000.0346000.0450000.0342000.0254000.0396000.0530000.0375000.051000.0
Percentage of OtherSundryLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PurchaseCommitmentRemainingMinimumAmountCommitted us-gaap:BalanceSheetLocation

us-gaap:PurchaseCommitmentRemainingMinimumAmountCommitted

us-gaap:AccruedLiabilities


Purchase
Period End2021-06-302021-03-312020-12-312020-09-30
Value4300000.03600000.03600000.03200000.0
Percentage of PurchaseCommitmentRemainingMinimumAmountCommitted100.0100.0100.0100.0

us-gaap:PurchaseObligation

us-gaap:PurchaseObligation


Purchase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value1211109.24.04.4592.8
Percentage of PurchaseObligation100.0100.0100.0100.0100.0100.0100.0

us-gaap:PurchaseObligationDueInNextTwelveMonths

us-gaap:PurchaseObligationDueInNextTwelveMonths


Purchase
Period End2020-12-31
Value10
Percentage of PurchaseObligationDueInNextTwelveMonths100.0

us-gaap:PurchaseObligationFutureMinimumPaymentsRemainderOfFiscalYear

us-gaap:PurchaseObligationFutureMinimumPaymentsRemainderOfFiscalYear


Purchase
Period End2021-06-302021-03-312020-09-30
Value11119.155
Percentage of PurchaseObligationFutureMinimumPaymentsRemainderOfFiscalYear100.0100.0100.0

us-gaap:RestrictedCashCurrent

us-gaap:RestrictedCashCurrent


Restricted
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-06-302019-03-312018-12-312018-06-302018-03-31
Value1352000.01352000.01352000.01352000.0001352000.01352000.0000
Percentage of RestrictedCashCurrent100.0100.0100.0100.00.00.0100.0100.00.00.00.0

us-gaap:RestrictedCashNoncurrent

us-gaap:RestrictedCashNoncurrent


Restricted
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1352000.01352000.01352000.01352000.02704000.02704000.02704000.02704000.02704000.02704000.04056000.04056000.04056000.04056000.04056000.0
Percentage of RestrictedCashNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RestructuringAndRelatedCostCostIncurredToDate1

us-gaap:RestructuringAndRelatedCostCostIncurredToDate1


Restructuring
Period End2020-12-31
Value16
Percentage of RestructuringAndRelatedCostCostIncurredToDate1100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant us-gaap:PlanName

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant

prta:A2018LongTermIncentivePlan


Share
Period End2020-12-312020-03-31
Value1669600.041972.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant100.0100.0

prta:A2020EmploymentInducementIncentivePlan


Share
Period End2021-06-302020-06-302020-02-25
Value50000.000
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant0.00.00.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-312020-09-30
Value14.314.625.4525.93
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice100.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value304814.6561.9942.4262.666110.722.3683.272.1693.7644.88230
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue


Share
Period End2021-06-302021-03-312020-12-312020-09-30
Value288774.5121.986
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue100.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-312020-09-30
Value16.7816.1520.7521.34
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice100.0100.0100.0100.0

us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRange

us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions

prta:RangeEight


Share
Period End2020-12-312019-12-312018-12-31
Value468980.05750.0129200.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions100.0100.0100.0

prta:RangeEleven


Share
Period End2020-12-31
Value4884400.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions1041.5

prta:RangeFive


Share
Period End2020-12-312019-12-312018-12-31
Value1384100.0960870.015000.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions295.116710.811.6

prta:RangeFour


Share
Period End2020-12-312019-12-312018-12-31
Value385980.0887410.00
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions82.315433.20.0

prta:RangeNine


Share
Period End2020-12-312019-12-312018-12-31
Value19791.013541.07291.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions4.2235.55.6

prta:RangeOne


Share
Period End2020-12-312019-12-312018-12-31
Value755910.0537220.0572060.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions161.29342.9442.8

prta:RangeSeven


Share
Period End2020-12-312019-12-312018-12-31
Value864840.0585910.0536950.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions184.410189.8415.6

prta:RangeSix


Share
Period End2020-12-312019-12-312018-12-31
Value971470.0642020.0525620.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions207.111165.6406.8

prta:RangeTen


Share
Period End2020-12-312019-12-312018-12-31
Value15000.015000.058879.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions3.2260.945.6

prta:RangeTwo


Share
Period End2020-12-312019-12-312018-12-31
Value18416.023666.00
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions3.9411.60.0

us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRange

us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions

prta:RangeEight


Share
Period End2020-12-312019-12-312018-12-31
Value488400.07500.0172140.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions100.0100.0100.0

prta:RangeEleven


Share
Period End2020-12-31
Value8744800.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions1790.5

prta:RangeFive


Share
Period End2020-12-312019-12-312018-12-31
Value2209100.01308300.0718400.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions452.317444.3417.3

prta:RangeFour


Share
Period End2020-12-312019-12-312018-12-31
Value1034300.02280000.02500.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions211.830399.71.5

prta:RangeOne


Share
Period End2020-12-312019-12-312018-12-31
Value988610.0735220.0666560.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions202.49802.9387.2

prta:RangeSeven


Share
Period End2020-12-312019-12-312018-12-31
Value896380.0756370.0951960.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions183.510085.0553.0

prta:RangeSix


Share
Period End2020-12-312019-12-312018-12-31
Value1158000.0715870.0716340.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions237.19544.9416.1

prta:RangeTen


Share
Period End2020-12-312019-12-312018-12-31
Value15000.015000.061250.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions3.1200.035.6

prta:RangeThree


Share
Period End2020-12-312019-12-312018-12-31
Value1148400.0778650.0807360.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions235.110382.0469.0

prta:RangeTwo


Share
Period End2020-12-312019-12-312018-12-31
Value781500.0386500.02605200.0
Percentage of ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions160.05153.31513.4

us-gaap:SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1 us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRange

us-gaap:SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1

prta:RangeEight


Sharebased
Period End2020-12-312019-12-312018-12-31
Value55.2159.8756.73
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1100.0100.0100.0

prta:RangeEleven


Sharebased
Period End2020-12-31
Value25.45
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice146.1

prta:RangeFive


Sharebased
Period End2020-12-312019-12-312018-12-31
Value15.0428.1533.1
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice127.247.058.3

prta:RangeFour


Sharebased
Period End2020-12-312019-12-312018-12-31
Value13.4315.040
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice124.325.10.0

prta:RangeOne


Sharebased
Period End2020-12-312019-12-312018-12-31
Value7.466.516.51
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice113.510.911.5

prta:RangeSeven


Sharebased
Period End2020-12-312019-12-312018-12-31
Value41.6754.4852.76
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice175.591.093.0

prta:RangeSix


Sharebased
Period End2020-12-312019-12-312018-12-31
Value29.0937.4836.08
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice152.762.663.6

prta:RangeTwo


Sharebased
Period End2020-12-312019-12-312018-12-31
Value11.6311.990
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice121.120.00.0

us-gaap:SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1 us-gaap:ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRange

us-gaap:SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1

prta:RangeEight


Sharebased
Period End2020-12-312019-12-312018-12-31
Value55.2159.956.6
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1100.0100.0100.0

prta:RangeEleven


Sharebased
Period End2020-12-31
Value20.42
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance137.0

prta:RangeFive


Sharebased
Period End2020-12-312019-12-312018-12-31
Value15.0429.1633.1
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance127.248.758.5

prta:RangeFour


Sharebased
Period End2020-12-312019-12-312018-12-31
Value13.2915.0433.06
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance124.125.158.4

prta:RangeOne


Sharebased
Period End2020-12-312019-12-312018-12-31
Value8.057.227.29
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance114.612.112.9

prta:RangeSeven


Sharebased
Period End2020-12-312019-12-312018-12-31
Value41.6254.4353.02
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance175.490.993.7

prta:RangeSix


Sharebased
Period End2020-12-312019-12-312018-12-31
Value29.5437.6535.78
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance153.562.963.2

prta:RangeThree


Sharebased
Period End2020-12-312019-12-312018-12-31
Value12.1513.5325.95
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance122.022.645.8

prta:RangeTwo


Sharebased
Period End2020-12-312019-12-312018-12-31
Value11.0710.7115.04
Percentage of SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance120.117.926.6

us-gaap:UndistributedEarningsOfForeignSubsidiaries us-gaap:IncomeTaxAuthorityName

us-gaap:UndistributedEarningsOfForeignSubsidiaries

us-gaap:InternalRevenueServiceIRS


Undistributed
Period End2020-12-312019-12-312018-12-31
Value906332
Percentage of UndistributedEarningsOfForeignSubsidiaries100.0100.0100.0

Line plots across dimensions of each concept


TTM Greenblatt ROC
_
(None,)
T T M  Greenblatt  R O C_
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ProductOrService
(None,)
Revenue From Contract With Customer Excluding Assessed Taxus-gaap: Product Or Service
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents
(None,)
Stockholders Equity Including Portion Attributable To Noncontrolling Interestus-gaap: Statement Equity Components
us-gaap:StockIssuedDuringPeriodValueNewIssues
us-gaap:StatementEquityComponents
(None,)
Stock Issued During Period Value New Issuesus-gaap: Statement Equity Components
us-gaap:ShareBasedCompensation
us-gaap:IncomeStatementLocation
(None,)
Share Based Compensationus-gaap: Income Statement Location