Document And Entity Information
ecd_TrdArrIndTitle
Trading Arrangement, Individual Title
Marketable Securities, Policy [Policy Text Block]
Statistical Measurement [Axis]
ecd_TrdArrIndName
Trading Arrangement, Individual Name
Note To Financial Statement Details Textual
ecd_TrdArrExpirationDate
Trading Arrangement Expiration Date
Significant Accounting Policies
Oxford Finance Limited Liability Company [Member]
Represents Oxford finance limited liability company.
ecd_TrdArrAdoptionDate
Trading Arrangement Adoption Date
Note 2 - Significant Accounting Policies
ecd_NonRule10b51ArrTrmntdFlag
Non-Rule 10b5-1 Arrangement Terminated [Flag]
Note 3 - Accounts Receivable, Net
pbyi_AccruedVariableConsiderationCurrent
Accrued variable consideration
Represents current accrued variable consideration.
ecd_NonRule10b51ArrAdoptedFlag
Non-Rule 10b5-1 Arrangement Adopted [Flag]
Note 4 - Prepaid Expenses and Other
pbyi_AccruedClinicalExpensesCurrent
Accrued other clinical development
Represents current accrued clinical expenses.
Trading Arrangements, by Individual [Table]
Note 5 - Leases
pbyi_AccruedProfessionalFeesLiabilityCurrent
Accrued professional fees
Represents current accrued professional fees liability.
Material Terms of Trading Arrangement [Text Block]
Note 6 - Property and Equipment, Net
pbyi_AccruedManufacturingCostsCurrent
Accrued manufacturing costs
Represents current accrued manufacturing costs.
Note 7 - Intangible Assets, Net
Schedule of Deferred Financing Costs [Table Text Block]
Tabular disclosure of deferred financing costs.
Equity Incentive Plan Twenty Eleven [Member]
Represents equity incentive plan 2011.
Note 8 - Accrued Expenses
Financial Instrument [Axis]
pbyi_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsInitialContractualTerm
Share-based Compensation Arrangement By Share-based Payment Award, Options Initial Contractual Term (Year)
Represents options initial contractual term for share-based compensation arrangement by share-based payment award.
Note 9 - Debt
Non-vested Stock Options [Member]
Represents non-vested stock options.
Note 10 - Stockholders' Equity
Secured Promissory Notes [Member]
Represents secured promissory notes.
Note 2 - Significant Accounting Policies - Segment Information (Details)
us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Unrealized losses
Unrealized gains
Note 2 - Significant Accounting Policies - Potentially Dilutive Securities Not Included in Calculation of Diluted Net Loss per Share (Details)
Statistical Measurement [Domain]
Note 2 - Significant Accounting Policies - Summary of Reconciliation of Numerators and Denominators of Basic and Diluted Net Income (Loss) Per Share of Common Stock Computations (Details)
Maximum [Member]
ecd_TrdArrSecuritiesAggAvailAmt
Trading Arrangement, Securities Aggregate Available Amount
Note 2 - Significant Accounting Policies - Assets Measured at Fair Value on Recurring Basis (Details)
Note 2 - Significant Accounting Policies - Summary of Cash Equivalents and Short-term Investment (Details)
Note 2 - Significant Accounting Policies - Inventory Balance (Details)
Prepaid Expense and Other Assets [Text Block]
The entire disclosure for prepaid expense and other assets.
Litigation Case [Domain]
Note 3 - Accounts Receivable, Net - Schedule of Accounts Receivable, Net (Details)
us-gaap_IncreaseDecreaseInAccountsReceivable
Accounts receivable, net
Note 4 - Prepaid Expenses and Other - Prepaid Expenses and Other (Details)
Retirement Plan Type [Domain]
Note 5 - Leases - Supplemental Cash Flow Information Related to Leases (Details)
Employee and Nonemployee Stock Option [Member]
Represents employee and nonemployee stock option.
Note 5 - Leases - Future Minimum Lease Payments (Details)
Note 6 - Property and Equipment, Net - Property and Equipment (Details)
Retirement Plan Type [Axis]
Note 7 - Intangible Assets, Net - Intangible Assets (Details)
Note 8 - Accrued Expenses - Composition of Current and Long-term Accrued Expenses (Details)
Note 9 - Debt - Schedule of Long Term Debt (Details)
Note 9 - Debt - Schedule of Long Term Debt (Details) (Parentheticals)
Note 9 - Debt - Schedule of Debt Issuance Costs and Discounts (Details)
Note 10 - Stockholders' Equity - Options Award Assumptions (Details)
Business Description and Basis of Presentation [Text Block]
Note 10 - Stockholders' Equity - Stock-based Compensation Expense (Details)
Note 10 - Stockholders' Equity - Stock-based Compensation Expense 2 (Details)
Note 10 - Stockholders' Equity - Stock Option Activity (Details)
Note 10 - Stockholders' Equity - Restricted Stock Units (Details)
Notes To Financial Statements
Alessandra Cesano, Board Member [Member]
Represents the board member Alessandra Cesano.
Notes To Financial Statements [Abstract]
Allison Dorval, Board Member [Member]
Represents the board member Allison Dorval.
Counterparty Name [Axis]
us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice
Expired, weighted average exercise price (in dollars per share)
Granted, weighted average exercise price (in dollars per share)
Adrian Senderowicz, Board Member [Member]
Represents the board member Adrian Senderowicz.
us-gaap_PrepaidExpenseAndOtherAssets
Totals
Financial Instruments [Domain]
us-gaap_LesseeOperatingLeaseDiscountRate
Lessee, Operating Lease, Discount Rate
Troy Wilson, Board Member [Member]
Troy Wilson.
Litigation Case [Axis]
Leasehold Improvements [Member]
Counterparty Name [Domain]
us-gaap_IncreaseDecreaseInInventories
Inventory, net
Award Type [Axis]
Segment Reporting [Table Text Block]
Adjustments to reconcile net income to net cash provided by operating activities:
Plan Name [Axis]
us-gaap_Liabilities
Total liabilities
Liability for Claims and Claims Adjustment Expense [Table]
Plan Name [Domain]
us-gaap_LiabilitiesAndStockholdersEquity
Total liabilities and stockholders’ equity
Consolidation Items [Axis]
Share-based compensation expense
Cash and Cash Equivalents [Axis]
Commercialization
us-gaap_ShareBasedCompensation
Stock-based compensation
Selling, general and administrative
Consolidation Items [Domain]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)
Lessee, Lease, Description [Table]
Medical Affairs [Member]
Relating to medical affairs.
Location, Statement of Income, Balance [Axis]
Other Research and Development [Member]
Relating to other research and development.
Changes in operating assets and liabilities:
Accounts payable
us-gaap_IncreaseDecreaseInAccountsPayable
Europe [Member]
us-gaap_FiniteLivedIntangibleAssetUsefulLife
Intangible Asset, Finite-Lived, Useful Life (Year)
us-gaap_RestrictedCash
Restricted Cash
pbyi_IncreaseDecreaseInOperatingLeaseAssetsAndLiabilitiesNet
Operating lease assets and liabilities, net
Amount of increase (decrease) in operating lease assets after deduction of operating lease liabilities
Restricted cash, current
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
Net increase (decrease) in cash, cash equivalents, and restricted cash
Cash Equivalents
New Accounting Pronouncements, Policy [Policy Text Block]
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations
Cash, cash equivalents and restricted cash, beginning of period
Cash, cash equivalents and restricted cash, end of period
US Government Agencies Debt Securities [Member]
Concentration Risk, Credit Risk, Policy [Policy Text Block]
Antidilutive Securities, Name [Domain]
Statement [Table]
Operating cash flows used for operating leases (in thousands)
us-gaap_PrepaidInsurance
Insurance
Prepaid Taxes
Other
us-gaap_PrepaidExpenseOtherNoncurrent
Prepaid expenses, current
Total, long-term
us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Debt Instrument, Basis Spread on Variable Rate
Investments
us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Line of Credit Facility, Maximum Borrowing Capacity
Intangible assets, net
Total intangible assets, net
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Nonvested shares (in shares)
Nonvested shares (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
Nonvested, Beginning balance, Weighted Average Grant-Date Fair Value (in dollars per share)
Nonvested, Beginning balance, Weighted Average Grant-Date Fair Value (in dollars per share)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Granted shares (in shares)
Granted, Weighted Average Grant-Date Fair Value (in dollars per share)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)
Long-Term Debt, Type [Axis]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Forfeited shares (in shares)
Product and Service [Domain]
Product and Service [Axis]
us-gaap_PropertyPlantAndEquipmentUsefulLife
Property, Plant and Equipment, Useful Life (Year)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue
Vested, Weighted Average Grant-Date Fair Value (in dollars per share)
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Vested shares (in shares)
us-gaap_RepaymentsOfDebt
Repayments of Debt
Payment of debt
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue
Total minimum lease payments
Weighted average discount rate
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths
2027
Commercial Paper [Member]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive
2031
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod
Expired, shares (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)
us-gaap_OperatingLeaseExpense
Operating Lease, Expense
us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear
2026
Exercisable, shares (in shares)
Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]
Exercisable, weighted average exercise price (in dollars per share)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)
Balance, shares (in shares)
Balance, shares (in shares)
Measurement Frequency [Axis]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree
2029
Commitments and Contingencies Disclosure [Text Block]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo
2028
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Balance, weighted average exercise price (in dollars per share)
Outstanding, weighted average exercise price (in dollars per share)
Nature of Expense [Axis]
Statement [Line Items]
pbyi_SubleaseAgreementPotentialMilestonePayments
Sublease Agreement, Potential Milestone Payments
Represents potential milestone payments for sublease agreement.
Fair Value Hierarchy and NAV [Axis]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour
2030
Outstanding, aggregate intrinsic value
Common stock, shares issued (in shares)
Award Type [Domain]
Common stock, shares outstanding (in shares)
Balance (in shares)
Balance (in shares)
Risk-free interest rate
Common stock, shares authorized (in shares)
Common Stock, Shares Authorized (in shares)
us-gaap_IncreaseDecreaseInPrepaidExpensesOther
Prepaid expenses and other
Expected volatility
Dividend yield
Schedule of Accrued Liabilities [Table Text Block]
pbyi_PotentialMilestonePayments
Potential Milestone Payments
The value of potential milestone payments.
us-gaap_ExtinguishmentOfDebtAmount
Less: debt repayment
Common stock - $0.0001 par value per share; 100,000,000 shares authorized; 51,102,687 shares issued and outstanding at June 30, 2026 and 50,408,023 issued and outstanding at December 31, 2025
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two
Fair Value of Financial Instruments, Policy [Policy Text Block]
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One
Schedule of Inventory, Current [Table Text Block]
Cash, Cash Equivalent, and Investment [Table Text Block]
us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)
pbyi_DebtInstrumentPeriodicPaymentExitPayment
Debt Instrument, Periodic Payment, Exit Payment
Represents the amount of periodic exit fees paid.
Accounts payable
Exit payment
Represents the amount of exit fees paid in a period.
us-gaap_PolicyTextBlockAbstract
Accounting Policies
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Remainder of Fiscal Year
us-gaap_DisclosureTextBlockAbstract
Notes to Financial Statements
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four
us-gaap_TableTextBlock
Notes Tables
us-gaap_AccruedBonusesCurrent
Accrued bonus
Computer Equipment [Member]
us-gaap_ComprehensiveIncomeNetOfTax
Comprehensive income
us-gaap_AccruedRoyaltiesCurrent
Accrued royalties
us-gaap_AccruedProfessionalFeesCurrent
Accrued legal fees
Accrued expenses
Totals
pbyi_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsGross
Debt issuance costs and discounts
Amount of gross unamortized debt discount (premium) and debt issuance costs.
us-gaap_EmployeeRelatedLiabilitiesCurrent
Accrued compensation
Significant Accounting Policies [Text Block]
The 2011 and 2017 Plans [Member]
Related to the 2011 and 2017 plans.
pbyi_CashCashEquivalentsAndMarketableSecurities
Cash, Cash Equivalents, and Marketable Securities
The value of cash, cash equivalents and marketable securities.
Maturity of available-for-sale securities
us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount
Less: imputed interest
Outstanding, weighted average remaining contractual term (Year)
Lease liabilities, long-term
Total lease liabilities
us-gaap_OtherAccruedLiabilitiesCurrent
Other
Lease liabilities, current
Fair Value, Assets Measured on Recurring Basis [Table Text Block]
Current portion of long-term debt
Less: current portion
Vested and expected to vest, weighted average remaining contractual term (Year)
Expected life in years (Year)
Exercisable, weighted average remaining contractual term (Year)
Total long-term debt, net
Investments, amortized cost
us-gaap_LongTermDebt
Long-Term Debt
Statement of Stockholders' Equity [Abstract]
Statement of Comprehensive Income [Abstract]
Class of Warrant or Right [Axis]
Class of Warrant or Right [Domain]
Statement of Cash Flows [Abstract]
Long-Term Debt, Type [Domain]
Stockholders’ equity:
Equity Components [Axis]
Share-Based Payment Arrangement [Policy Text Block]
Equity Component [Domain]
us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)
Fair Value, Inputs, Level 2 [Member]
Fair Value, Inputs, Level 3 [Member]
CALIFORNIA
Equity [Text Block]
Fair Value, Inputs, Level 1 [Member]
AOCI Attributable to Parent [Member]
Additional Paid-in Capital [Member]
Cash equivalents, unrealized gain
Amount, before tax, of unrealized gains on cash and cash equivalents.
Retained Earnings [Member]
Cost of sales
Property and equipment, net
Property and equipment, net
Compensation and Employee Benefit Plans [Text Block]
Property, Plant and Equipment, Gross
Property and equipment purchases in accounts payable
Provision for credit loss recovery
Accounts Receivable, Credit Loss Expense (Reversal)
Deferred tax assets
Property, Plant, and Equipment [Policy Text Block]
Auerbach Warrant [Member]
Represents Auerbach Warrant.
Development and Commercialization of Innovative Products to Enhance Cancer Care [Member]
Represents development and commercialization of innovative products to enhance cancer care.
Furniture and Fixtures [Member]
Stock-based compensation
Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]
Accounts Payable and Accrued Liabilities Disclosure [Text Block]
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Share-Based Payment Arrangement, Option [Member]
Supplemental disclosure of cash flow information:
Current liabilities:
us-gaap_CurrentIncomeTaxExpenseBenefit
Income tax expense
us-gaap_LiabilitiesCurrent
Total current liabilities
us-gaap_LettersOfCreditOutstandingAmount
Letters of Credit Outstanding, Amount
Accounts receivable
Marketable securities
Legal Costs, Policy [Policy Text Block]
Income taxes paid
Lessee, Leases [Policy Text Block]
Other Commitments [Table]
us-gaap_GainLossOnSaleOfPropertyPlantEquipment
Loss on disposal of property and equipment
us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Less: accumulated depreciation
Accumulated other comprehensive (loss) income
us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
Less: accumulated amortization
Pfizer License Agreement [Member]
Relating to the Pfizer license agreement
pbyi_UpfrontLicenseFee
Upfront License Fee
Amount of upfront license fee.
Takeda [Member]
Relating to Takeda.
General and administrative
us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Net income before income taxes
Additional paid-in capital
Debt Disclosure [Text Block]
Segment Reporting, Policy [Policy Text Block]
us-gaap_PrepaidExpenseAndOtherAssetsNoncurrent
Prepaid expenses and other, long-term
Prepaid Expense and Other Assets, Noncurrent
Use of Estimates, Policy [Policy Text Block]
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)
Shares issued or restricted stock units vested under employee stock plans
us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Purchase of property and equipment
Lessee, Operating Leases [Text Block]
Total debt, inclusive of $2.0 million exit payment
us-gaap_DebtInstrumentFaceAmount
Debt Instrument, Face Amount
Current assets:
Schedule of Debt [Table Text Block]
us-gaap_AssetsCurrent
Total current assets
Shares issued or restricted stock units vested under employee stock plans (in shares)
Restricted Stock Units (RSUs) [Member]
us-gaap_LitigationSettlementAmountAwardedFromOtherParty
Litigation Settlement, Amount Awarded from Other Party
Debt Instrument, Name [Domain]
Assets that Continue to be Recognized, Transferred Financial Assets and Other Financial Assets Managed Together [Table]
us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares)
Maturity date
us-gaap_DebtInstrumentInterestRateStatedPercentage
Debt Instrument, Interest Rate, Stated Percentage
us-gaap_Depreciation
Depreciation
us-gaap_DebtInstrumentInterestRateEffectivePercentage
Debt Instrument, Interest Rate, Effective Percentage
Related and Nonrelated Parties [Axis]
us-gaap_DebtInstrumentUnamortizedDiscount
Debt Instrument, Unamortized Discount, Total
us-gaap_DebtInstrumentPeriodicPaymentPrincipal
Debt Instrument, Periodic Payment, Principal
Schedule of Long-Term Debt Instruments [Table]
Debt Instrument [Axis]
us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet
Less: unamortized debt issuance costs and discounts
Included in current portion of debt
Adjusted Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
The adjusted rate on U.S. dollar, constant-notional interest rate swap that has its variable-rate leg referenced to Secured Overnight Financing Rate (SOFR) with no additional spread over SOFR on variable-rate leg.
Operating activities:
Investing activities:
us-gaap_NetCashProvidedByUsedInOperatingActivities
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation
Net cash provided by operating activities
Raw materials
Work-in-process
Financing activities:
us-gaap_NetCashProvidedByUsedInInvestingActivities
Net cash provided by (used by) investing activities
Finished goods
us-gaap_NetCashProvidedByUsedInFinancingActivities
Net cash used in financing activities
us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt
Purchase of available-for-sale securities
us-gaap_AssetsFairValueDisclosure
Totals
Share-Based Payment Arrangement, Activity [Table Text Block]
Operating Segments [Member]
Accounting Policies [Abstract]
Segments [Domain]
us-gaap_DeferredFinanceCostsGross
Debt Issuance Costs, Gross
us-gaap_AccumulatedAmortizationDeferredFinanceCosts
Less: accumulated amortization
Segments [Axis]
Income Statement [Abstract]
us-gaap_NumberOfReportableSegments
Number of Reportable Segments
Net income
Net Income (Loss) Attributable to Parent
Net income
us-gaap_AmortizationOfFinancingCosts
Amortization of Debt Issuance Costs
us-gaap_AmortizationOfIntangibleAssets
Intangible Asset, Finite-Lived, Amortization Expense
Total operating costs and expenses
Total operating costs and expenses
Net proceeds from shares issued under employee stock plans
Accounting Standards Update and Change in Accounting Principle [Table]
Income Tax, Policy [Policy Text Block]
Supplemental disclosures of non-cash investing and financing activities:
Related and Nonrelated Parties [Domain]
Collaborative Arrangement and Arrangement Other than Collaborative [Axis]
Vested and expected to vest, shares (in shares)
Vested and expected to vest, aggregate intrinsic value
Vested and expected to vest, weighted average exercise price (in dollars per share)
Fair Value Hierarchy and NAV [Domain]
Measurement Frequency [Domain]
Other income (expenses):
Statement of Financial Position [Abstract]
us-gaap_NonoperatingIncomeExpense
Total other income (expenses), net
us-gaap_TangibleAssetImpairmentCharges
Tangible Asset Impairment Charges
Fair Value, Recurring [Member]
Warrant [Member]
Document Type
Document Information [Line Items]
Document Quarterly Report
us-gaap_LesseeOperatingLeaseTermOfContract
Lessee, Operating Lease, Term of Contract (Year)
us-gaap_DefinedContributionPlanCostRecognized
Defined Contribution Plan, Cost
us-gaap_LesseeOperatingLeaseRenewalTerm
Lessee, Operating Lease, Renewal Term (Year)
Weighted-average remaining lease term (in years) (Year)
Document Information [Table]
us-gaap_IncreaseDecreaseInOtherCurrentAssets
Other current assets
Anti-dilutive securities not included in calculation of diluted net loss per share (in shares)
Antidilutive Securities [Axis]
Net effect of dilutive common stock equivalents (in shares)
Entity Interactive Data Current
Document Transition Report
Weighted-average shares of common stock outstanding—diluted (in shares)
Weighted average common stock outstanding for diluted net income per share (in shares)
Operating costs and expenses
Weighted average common stock outstanding for basic net income per share (in shares)
Weighted-average shares of common stock outstanding—basic (in shares)
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]
Basic (in dollars per share)
Net income per share of common stock—basic (in dollars per share)
Research and Development Expense, Policy [Policy Text Block]
Research and development
Earnings Per Share, Policy [Policy Text Block]
Collaborative Arrangement and Arrangement Other than Collaborative [Domain]
Subsidiary of Common Parent [Member]
Acquired and in-licensed rights
us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross
Shares Issued, Shares, Share-Based Payment Arrangement, before Forfeiture (in shares)
Document Fiscal Period Focus
Document Fiscal Year Focus
Depreciation and amortization
Amendment Flag
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Common Stock [Member]
us-gaap_SubleaseIncome
Sublease Income
pbyi_CashAndCashEquivalentsAccumulatedGrossUnrealizedLossBeforeTax
Cash equivalents, unrealized losses
Amount, before tax, of unrealized losses on cash and cash equivalents.
Athyrium Notes [Member]
Relating to Athyrium Notes.
Document Period End Date
Property, Plant, and Equipment [Text Block]
Long-Lived Asset, Class [Domain]
Granted, shares (in shares)
Legal Entity [Axis]
Entity File Number
Entity Tax Identification Number
Entity [Domain]
Entity Central Index Key
Entity Registrant Name
Entity Current Reporting Status
Entity Incorporation, State or Country Code
Current Fiscal Year End Date
Fair Value Measurement, Policy [Policy Text Block]
Entity Filer Category
Entity Shell Company
Entity Emerging Growth Company
Entity Small Business
Cash and Cash Equivalents [Domain]
us-gaap_OperatingIncomeLoss
Income from operations
Investments [Domain]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
Operating costs and expenses:
Entity Address, State or Province
Entity Address, City or Town
us-gaap_InterestExpenseNonoperating
Interest expense
Accumulated deficit
Entity Address, Address Line One
City Area Code
Local Phone Number
Entity Address, Postal Zip Code
Accrued expenses and other
Title of 12(b) Security
Security Exchange Name
Trading Symbol
Class of Stock [Axis]
Investments, fair value
Variable Rate [Axis]
Variable Rate [Domain]
Revenue [Policy Text Block]
Entity Common Stock, Shares Outstanding
Other comprehensive loss:
Other assets, current
Unrealized loss on available-for-sale securities, tax
Unrealized loss on available-for-sale securities, net of tax of $0
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]
Equity, Capital Unit or Share [Table]
Research and Development Arrangement, Contract to Perform for Others, Type [Axis]
us-gaap_PaymentsOfDebtExtinguishmentCosts
Payment of exit costs
Exercisable, aggregate intrinsic value
Property, Plant, and Equipment [Table]
Common stock, par value (in dollars per share)
Common Stock, Par or Stated Value Per Share (in dollars per share)
Research and Development Arrangement, Contract to Perform for Others, Type [Domain]
Other income
Long-Lived Asset, Class [Axis]
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]
Insurance
Represents the amount of noncurrent prepaid insurance.
us-gaap_Assets
Total assets
Cash and Cash Equivalents, Policy [Policy Text Block]
Cash and cash equivalents
Cash Equivalents [Member]
Geographical [Domain]
Post-marketing commitment liability
Represents current post marketing commitment liability.
Geographical [Axis]
Totals, amortized cost
us-gaap_OtherPrepaidExpenseCurrent
Other
us-gaap_AccountsReceivableGross
Total accounts receivable
us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
Common Stock, Capital Shares Reserved for Future Issuance (in shares)
Diluted (in dollars per share)
Net income per share of common stock—diluted (in dollars per share)
us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay
pbyi_NumberOfSubsidiaries
Number of Subsidiaries
Represents number of subsidiaries.
pbyi_DebtInstrumentPeriodicPaymentExitPaymentPercent
Debt Instrument, Periodic Payment, Exit Payment, Percent
The percent exit payment made with periodic payments of debt instrument.
pbyi_CashAndCashEquivalentsAndRestrictedCashInExcessOfInsuredLimits
Cash and Cash Equivalents, and Restricted Cash In Excess of Insured Limits
Represents cash and cash equivalents and restricted noncash in excess of insured limits.
Telephone Equipment [Member]
Represents information related to telephone equipment.
Post-marketing commitment liability
pbyi_IncreaseDecreaseInPostmarketingCommitmentLiability
Represents increase (decrease) in post-marketing commitment liability.
Intangible Asset [Text Block]
Accounts and Financing Receivables [Table]
Investment Type [Axis]
Consolidation, Policy [Policy Text Block]
Interest income
Interest paid
Unvested Restricted Stock Units [Member]
Represents information related to unvested restricted stock units.
Individual [Axis]
Intangible Asset, Finite-Lived [Table Text Block]
Intangible Asset, Finite-Lived [Table]
AstraZeneca Litigation [Member]
Judicial proceeding, alternative dispute resolution or claim. For example, but not limited to, name of case, category of litigation, or other differentiating information.
License Fees and Intangible Assets [Policy Text Block]
Disclosure of accounting policy for license fees and intangible assets.
Interim Period, Costs Not Allocable [Domain]
pbyi_MilestonePayment
Milestone Payment
Represents payments for milestone.
Product [Member]
pbyi_PercentageOfUnpaidPortionOfMilestonePaymentsInterestRate
Percentage of Unpaid Portion of Milestone Payments Interest Rate
Represents percentage of unpaid portion of milestone payments interest rate.
First 3% of Each Participant's Contributions [Member]
Represents first 3% of each participants' contributions.
Royalty [Member]
Inventory
Inventory, Net
Total inventories
Second Two Percent Of Each Participants Contributions [Member]
Represents second two percent of each participants contributions.
Employment Inducement Incentive Award Plan Twenty Seventeen [Member]
Represents information related to employment inducement incentive award plan 2017.
All Individuals [Member]
Note Purchase Agreement [Member]
Represents information related to note purchase agreement.
pbyi_MilestonePaymentsMaximumAmount
Milestone Payments Maximum Amount
Represents maximum amount of milestone payments.
pbyi_OrdinarySharesOwnershipPercentage
Ordinary Shares Ownership Percentage
Represents percentage of ordinary shares ownership.
Corporate Bond Securities [Member]
Totals, fair value
Represents fair value of cash, cash equivalents and short-term investments.
pbyi_DebtInstrumentExitPaymentPercent
Debt Instrument, Exit Payment Percent
Represents the percentage of principal that makes up an exit payment.
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]
Trade accounts receivable
Represents trade accounts receivable net excluding license revenue receivable.
Prepaid Expense and Other Assets [Table Text Block]
Tabular disclosure of prepaid expense and other assets.
us-gaap_StockholdersEquity
Total stockholders’ equity
Balance
Balance
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue
Forfeited, Weighted Average Grant-Date Fair Value (in dollars per share)
Clinical Research [Member]
Represents information related to clinical research.
Accounts Receivable [Text Block]
The entire disclosure for accounts receivable.
Schedule of Accounts Receivable [Table Text Block]
Tabular disclosure of accounts receivable.
Royalty revenue receivable
Represents information related to royalty revenue receivable.
pbyi_PrepaidCROServicesNoncurrent
CRO services
Represents noncurrent prepaid CRO services.
pbyi_PrepaidOtherClinicalDevelopmentExpenseNoncurrent
Other clinical development
Represents noncurrent prepaid other clinical development expense.
pbyi_AreaOfLeasedProperty
Area of Leased Property (Square Foot)
Represents are of leased property.
CRO services
Represents current prepaid CRO services.
Other clinical development
Represents current prepaid other clinical development.
Professional fees
Represents current prepaid professional fees.
Lease Agreement Two [Member]
Represents lease agreement two.
Nature of Operation, Product Information, Concentration of Risk [Table]
Lease Agreement One [Member]
Represents lease agreement one.
Lessee, Operating Leases Related To Supplemental Cash Flow Information [Table Text Block]
Tabular disclosure of operating leases related to supplemental cash flow information for lessee.
pbyi_PolicyTable
pbyi_AreaOfSubleasedProperty
Area of Subleased Property (Square Foot)
Represents area of subleased property.
Lease right-of-use assets, net
Other liabilities, current
pbyi_LeaseOptionToExtendTerm
Lease Option To Extend Term (Year)
Represents lease option to extend term.
Insider Trading Arrangements [Table]
ecd_Rule10b51ArrTrmntdFlag
Rule 10b5-1 Arrangement Terminated [Flag]
Property, Plant, and Equipment [Table Text Block]
Total revenue
us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax
Revenue from Contract with Customer, Including Assessed Tax
ecd_Rule10b51ArrAdoptedFlag
Rule 10b5-1 Arrangement Adopted [Flag]
pbyi_AccruedDevelopmentCosts
Accrued CRO services
Represents accrued development costs.
Inventory, Policy [Policy Text Block]
Commitments and contingencies (Note 12)