Granted (in shares) Awards granted in period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Document Type Document Type ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Aggregate intrinsic value, Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Other income Other Nonoperating Income (Expense) Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Percentage of employee vested contribution Defined Contribution Plan, Employees Contribution, Vested Percentage Percentage vested of employee's contributions to defined contribution plan Retirement of treasury stock (in shares) Treasury Stock, Shares, Retired Treasury Stock Treasury Stock [Member] Marketable Securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Employee Benefit Plan Retirement Benefits [Text Block] Exercised (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Significant Unobservable Inputs, Level 3 Fair Value, Inputs, Level 3 [Member] Lease liabilities Increase (decrease) in lease liabilities Increase (decrease) in lease liabilities Range Statistical Measurement [Domain] Liabilities and stockholders' equity Liabilities and Equity [Abstract] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Boehringer Collaboration and License Agreement Boehringer Ingelheim International GmbH Collaboration And License Agreement [Member] Boehringer Ingelheim International GmbH Collaboration And License Agreement NIAID National Institute of Allergy and Infectious Diseases [Member] Represents a collaborators with which entity has an agreement related to contracts and research grants received from U.S. government agencies. Operating lease liabilities Deferred Tax Assets, Operating Lease Liabilities Deferred Tax Assets, Operating Lease Liabilities Security Exchange Name Security Exchange Name Non-refundable upfront payment, net of tax withholding Nonrefundable Upfront Fees, Net Of Tax Withholding Nonrefundable Upfront Fees, Net Of Tax Withholding Loss from operations Operating Income (Loss) Deferred revenue Deferred revenue, current Deferred Revenue, Current Total current liabilities Liabilities, Current Accounts Receivable Accounts Receivable [Policy Text Block] Beginning Balance (in dollars per share) Ending Balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Percentage of employee contribution to salary Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Assets Assets [Abstract] Number of extension options Lessee, Operating Lease, Number Of Renewal Options Lessee, Operating Lease, Number Of Renewal Options Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Accounting Policies [Abstract] Accounting Policies [Abstract] Incyte MGA012 Supply Agreement Incyte MGA012 Supply Agreement [Member] Incyte MGA012 Supply Agreement Thereafter Lessee, Operating Lease, Liability, to be Paid, after Year Five Furniture Furniture and Fixtures [Member] Entity Address, State or Province Entity Address, State or Province United States federal tax at statutory rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Operating lease payments Operating Lease, Payments Accounts payable Accounts Payable, Current Sublease income Sublease Income Accumulated deficit Retained Earnings (Accumulated Deficit) Operating lease, ROU Assets Operating Lease, Right-of-Use Asset Depreciation Deferred Tax Liabilities, Property, Plant and Equipment Collaboration and Other Agreements Collaboration And License Agreements Disclosure [Text Block] The entire disclosure for collaboration and license agreements. 2020 Lessee, Operating Lease, Liability, to be Paid, Year One Share-based compensation arrangement by share-based payment award, options, outstanding, number (in shares) Beginning Balance (in shares) Ending Balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number 2023 Lessee, Operating Lease, Liability, to be Paid, Year Four Unrecognized compensation cost related to non-vested stock-based compensation arrangements Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Impaired assets Impaired Assets to be Disposed of by Method Other than Sale, Carrying Value of Asset Customer [Axis] Customer [Axis] US Federal tax credits carry forward Tax Credit Carryforward, Amount Income Taxes Income Tax, Policy [Policy Text Block] Non-refundable upfront payment Non-refundable upfront payment Initial fee received from collaboration or license agreement. Net lease cost Lease, Cost Exercisable (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Common stock, par value (in dollars per share) Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Other comprehensive loss: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Fair value of shares vested Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value Share-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Construction in progress Construction in Progress, Gross Term of agreement (in years) Collaboration And License Agreement, Term Collaboration And License Agreement, Term Proceeds from stock option exercises and ESPP purchases Proceeds from Stock Options Exercised And ESPP Purchases Proceeds from Stock Options Exercised And ESPP Purchases Percentage of significant accounts receivable Concentration Risk, Percentage Options granted, maximum term Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Common stock maximum amount available for issuance Common Stock, Maximum Amount Available For Issuance Common Stock, Maximum Amount Available For Issuance Deferred income tax adjustments Effective Income Tax Rate Reconciliation, Deferred Tax Adjustments, Amount Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deferred tax adjustments. Statement [Line Items] Statement [Line Items] Incyte MGA012 Clinical Services Incyte MGA012 Clinical Services [Member] Incyte MGA012 Clinical Services Schedule of Stock Options and RSUs Excluded from the Calculation of Net Loss Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Class of Stock [Domain] Class of Stock [Domain] Indefinite Indefinite [Member] Indefinite Tax Period [Axis] Tax Period [Axis] Computer equipment Computer Equipment [Member] Unrealized gain on investments Unrealized Gain (Loss) on Investments Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Entity Voluntary Filers Entity Voluntary Filers Statement [Table] Statement [Table] Estimated Useful Lives Property Plant And Equipment Estimated Useful Life Table [Text Block] Property plant and equipment estimated useful life. Range [Axis] Statistical Measurement [Axis] Offset to research and development costs under collaboration arrangement Collaboration Arrangement Offset to Research and Development Costs Refers to collaboration arrangement offset to research and development costs. Research and Development Arrangement, Contract to Perform for Others, Type [Axis] Research and Development Arrangement, Contract to Perform for Others, Type [Axis] Undesignated preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Text Block [Abstract] Text Block [Abstract] Number of product candidates to develop Number Of Product Candidates Number Of Product Candidates Research and Development Arrangement, Contract to Perform for Others, Type [Domain] Research and Development Arrangement, Contract to Perform for Others, Type [Domain] Interest Income, Other Interest Income, Other Potential development and regulatory milestone payments Potential Development and Regulatory Milestone Payments Under Agreement Potential Development and Regulatory Milestone Payments Under Agreement At The Market Offering At The Market Offering [Member] At The Market Offering [Member] Entity Small Business Entity Small Business Servier Servier [Member] Counterparty in collaboration agreement Tax withholding Non-refundable Payment, Tax Withholding Non-refundable Payment, Tax Withholding Sale of common stock (in shares) Sale of Stock, Number of Shares Issued in Transaction Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Weighted-average remaining contractual term, Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Prepaid expenses and other current assets Prepaid Expense, Current Base period value Funded Value of Base Period Funded value of base period Proceeds from issuance of common stock, net of offering costs Proceeds from Issuance of Common Stock Proceeds from sales and maturities of marketable securities Proceeds from Sale and Maturity of Debt Securities, Available-for-sale Amendment Flag Amendment Flag Share-based compensation, number of shares authorized (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Research and Development Costs, Including Clinical Trial Accruals/Expenses Research and Development Expense, Policy [Policy Text Block] Estimated variable consideration Revenue, Information Used To Assess Variable Consideration, Amount Revenue, Information Used To Assess Variable Consideration, Amount Net cash provided by (used in) operating activities Net Cash Provided by (Used in) Operating Activities Revenue from collaborative agreements Revenue From Collaborative Agreements [Member] Revenue From Collaborative Agreements Zai Lab Clinical Supply Agreements Zai Lab Clinical Supply Agreements [Member] Zai Lab Clinical Supply Agreements Entity Central Index Key Entity Central Index Key Stock-based Compensation Compensation Related Costs, Policy [Policy Text Block] Potential milestone payment to third parties for intellectual property under agreement Potential Milestone Payment To Third Parties For Intellectual Property Under Agreement Potential Milestone Payment To Third Parties For Intellectual Property Under Agreement Financial Instruments [Domain] Financial Instruments [Domain] Tax Year 2025 To 2037 Tax Year 2025 To 2037 [Member] Tax Year 2025 To 2037 Operating lease ROU assets Deferred Tax Liabilities, Operating Lease Right Of Use Assets Deferred Tax Liabilities, Operating Lease Right Of Use Assets Common stock purchased by employees (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Amortized Cost Debt Securities, Available-for-sale, Amortized Cost Lease renewal term (in years) Lessee, Operating Lease, Renewal Term Gross Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Development milestones Development Milestones, Amount Development Milestones, Amount Statement of Cash Flows [Abstract] Amounts recognized Development milestones recognized Development And Regulatory Milestone Payments Under Agreement, Recognized Development And Regulatory Milestone Payments Under Agreement, Recognized Potential milestone payments and royalties on product sales Potential Milestone Payments and Royalties On Product Sales Potential Milestone Payments and Royalties On Product Sales Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Schedule of RSU Activity Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] Income Statement Location [Axis] Income Statement Location [Axis] Potential milestone payments and royalties on future sales Potential Milestone Payments and Royalties on Future Sales under Agreement Potential Milestone Payments and Royalties on Future Sales under Agreement Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Income Statement Location [Domain] Income Statement Location [Domain] Research credit, net Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount 2021 Lessee, Operating Lease, Liability, to be Paid, Year Two Milestone payment removed Milestone Payment Milestone Payment Deferred revenue Deferred Tax Assets, Deferred Income 2016 Employee Stock Purchase Plan Two Thousand Sixteen Employee Stock Purchase Plan [Member] Two Thousand Sixteen Employee Stock Purchase Plan [Member] Lease, Cost Lease, Cost [Table Text Block] Undesignated Preferred Stock Undesignated Preferred Stock [Member] Undesignated Preferred Stock [Member] 2022 Lessee, Operating Lease, Liability, to be Paid, Year Three Other assets Other Assets, Noncurrent Plan Name [Axis] Plan Name [Axis] Issuance of common stock, net of offering costs Stock Issued During Period, Value, New Issues Cash and cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Concentration Risk [Table] Concentration Risk [Table] Total assets Assets Beginning Balance (in shares) Ending Balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Follow-On Equity Offering Follow-On Equity Offering [Member] Follow-On Equity Offering Incyte Corporation (Incyte) Incyte Corporation [Member] Incyte Corporation [Member] Title of 12(b) Security Title of 12(b) Security Weighted-average grant-date fair value of options granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Antidilutive Securities [Axis] Antidilutive Securities [Axis] Amount of development progress recognized Development Progress And Regulatory Milestone Payments Under Agreement, Recognized Development Progress And Regulatory Milestone Payments Under Agreement, Recognized Investments, Debt and Equity Securities [Abstract] Concentration of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Proceeds of stock sale Sale of Stock, Consideration Received on Transaction Depreciation and amortization expense Depreciation, Depletion and Amortization Equity-based compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Eligible age to participate in plan Employees Eligible Age To Participate In Benefit Plan Refers to minimum eligible age of employee to participate in benefit plan. Product and Service [Axis] Product and Service [Axis] Total liabilities Liabilities Unrecognized compensation expense recognition period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Increased number of shares authorized (in shares) Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized After Increase Share based compensation arrangement by share based payment award number of shares authorized after increase. Present value adjustment Lessee, Operating Lease, Liability, Undiscounted Excess Amount Weighted-average remaining contractual term, Vested and expected to vest Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Commitments and Contingencies Disclosure [Abstract] Unrecognized interest or penalties Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Quoted Prices in Active Markets for Identical Assets, Level 1 Fair Value, Inputs, Level 1 [Member] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Accounts payable Increase (Decrease) in Accounts Payable Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Deferred revenue, net of current portion Deferred revenue included in long-term liabilities Deferred Revenue, Noncurrent I-Mab I-Mab Biopharma [Member] I-Mab Biopharma Zai Lab Limited (Zai Lab) Zai Lab Limited [Member] Zai Lab Limited Additional Paid-In Capital Additional Paid-in Capital [Member] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Class of Stock [Line Items] Class of Stock [Line Items] Accrued expenses Increase (Decrease) in Accrued Liabilities Asset Class [Axis] Asset Class [Axis] Adjustments to reconcile net loss to net cash provided by (used in) operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Balance (in shares) Balance (in shares) Shares, Issued Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Income Tax Disclosure [Abstract] Variable lease cost Variable Lease, Cost State taxes (net of federal benefit) Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Option exercise fee Option Exercise Fee Payment from collaborator upon exercise of option to develop and commercialize product. Research and development Research and Development Expense Weighted average exercise price (in dollars per share) Beginning Balance (in dollars per share) Ending Balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Comprehensive Loss Comprehensive Income, Policy [Policy Text Block] U.S. Federal Government Domestic Tax Authority [Member] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Concentration Risk Type [Axis] Concentration Risk Type [Axis] Cash proceeds from exercise of stock options Proceeds from Stock Options Exercised Property, equipment and software Property, Plant and Equipment, Gross Firm Commitment Public Underwritten Offer Firm Commitment Public Underwritten Offer [Member] Firm Commitment Public Underwritten Offer Revenues Revenue [Policy Text Block] Stock warrants (in shares) Collaborative Agreement Consideration Received Common Stock Warrants Number Of Shares Collaborative Agreement Consideration Received Common Stock Warrants Number Of Shares Remaining portion of net operating losses Operating Loss Carryforwards Not Subject To Limitation Operating loss carryforwards not subject to limitation. Collaboration and Other Agreements [Line Items] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Income Statement [Abstract] Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] Lease liabilities, net of current portion Operating Lease, Liability, Noncurrent Transaction price Collaborative Agreement Transaction Price Collaborative Agreement Transaction Price Over-Allotment Option Over-Allotment Option [Member] State net operating loss carryforward Deferred Tax Assets, Operating Loss Carryforwards, State and Local Stock plan related activity Stock Issued During Period Value Stock Plan Activity Value of shares issued due to stock plan related activity. Use of Estimates Use of Estimates, Policy [Policy Text Block] Current assets: Assets, Current [Abstract] Income Tax Authority [Domain] Income Tax Authority [Domain] Cash flows from investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Software Software and Software Development Costs [Member] Revenue from government agreements Revenue From Government Agreements [Member] Revenue From Government Agreements Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Consideration received common stock warrant exercise price (in usd per share) Collaborative Agreement Consideration Received Common Stock Warrant Exercise Price Per Share Collaborative Agreement Consideration Received Common Stock Warrant Exercise Price Per Share Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Undesignated preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Government-sponsored enterprises Government-sponsored enterprises US Government-sponsored Enterprises Debt Securities [Member] Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Reconciliation of Reported Estimated Income Tax Benefit Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Counterparty Name [Domain] Counterparty Name [Domain] Purchases of property, equipment and software Payments to Acquire Property, Plant, and Equipment City Area Code City Area Code Income Tax Authority [Axis] Income Tax Authority [Axis] Document Period End Date Document Period End Date Property, Plant and Equipment [Abstract] Debt Securities, Available-for-sale, Allowance for Credit Loss Debt Securities, Available-for-sale, Allowance for Credit Loss Total potential value Total potential value of agreement Refers to total potential value under agreement. Impairment of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Prepaid expenses Increase (Decrease) in Prepaid Expense Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Minimum annual increase (in shares) Common Stock Capital Shares Minimum Increase In Shares Reserved For Future Issuance Common Stock Capital Shares Minimum Increase In Shares Reserved For Future Issuance Federal U.S. net operating loss carryforward Deferred Tax Assets, Operating Loss Carryforwards, Domestic Weighted-Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price [Abstract] Share-based compensation Share-based Payment Arrangement, Noncash Expense Purchase of treasury stock Payment, Tax Withholding, Share-based Payment Arrangement Cover [Abstract] Orphan drug credit, net Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount Available-for-sale Debt Securities, Available-for-sale [Table Text Block] Collaboration and License Agreements [Abstract] Collaboration and License Agreements [Abstract] U.S. Federal and State Domestic Tax Authority and State and Local Jurisdiction [Member] [Member] Domestic Tax Authority and State and Local Jurisdiction [Member] [Member] Estimated useful lives Property, Plant and Equipment, Useful Life Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Deferred revenue Increase (Decrease) in Contract with Customer, Liability Leases Lessee, Operating Leases [Text Block] Marketable securities Investments Amortization of premiums and discounts on marketable securities Accretion (Amortization) of Discounts and Premiums, Investments Potential commercial milestone payments Potential Commercial Milestone Payments Under Agreement Potential Commercial Milestone Payments Under Agreement Net deferred income tax asset/(liability) Deferred Tax Assets, Net Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Securities Fair Value Debt Securities, Available-for-sale Total costs and expenses Costs and Expenses Equity Components [Axis] Equity Components [Axis] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Share-based Payment Arrangement [Abstract] Gross deferred income tax assets Deferred Tax Assets, Gross Minimum Minimum [Member] Lease liabilities Operating Lease, Liability, Current Total unrecognized compensation cost Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Potential proceeds from royalties percent Proceeds from Royalties, Percent Proceeds from Royalties, Percent Net operating losses limited for use utilized on an annual basis Operating Loss Carryforwards Annual Limitation Amount Amount of net operating loss which are limited for use, utilized on a annual basis. Forfeited or expired (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Schedule of Employee Stock Options Award Valuation Assumptions Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Entity Interactive Data Current Entity Interactive Data Current Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Equity Incentive Plan 2003 Equity Incentive Plan 2003 [Member] Equity Incentive Plan 2003 Revenues: Revenues [Abstract] Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Schedule of Stock Option Activity Share-based Payment Arrangement, Option, Activity [Table Text Block] Accounts receivable Accounts Receivable [Member] Servier Agreement - MGD007 Option Servier Agreement - MGD007 Option [Member] Servier Agreement - MGD007 Option Customer [Domain] Customer [Domain] Cumulative Effect, Period of Adoption, Adjustment Cumulative Effect, Period of Adoption, Adjustment [Member] Additional paid-in capital Additional Paid in Capital, Common Stock Fair value of warrants received Fair Value Of Warrants Received Fair Value Of Warrants Received Entity Registrant Name Entity Registrant Name Statement of Stockholders' Equity [Abstract] Concentration Risk [Line Items] Concentration Risk [Line Items] Assets [Abstract] Assets, Fair Value Disclosure [Abstract] Entitled milestone payments Entitled Milestone Payments Under Agreement Entitled Milestone Payments Under Agreement Income Tax Examination [Line Items] Income Tax Examination [Line Items] Gross deferred income tax liabilities Deferred Tax Liabilities, Gross Revenues, tax withholding Revenues, Tax Withholding Revenues, Tax Withholding Incyte MGA012 Agreement Incyte MGA012 Agreement [Member] Incyte MGA012 Agreement Proceeds from additional development funding options under agreement Exercised Additional Development Funding Options Under Agreement Exercised Additional Development Funding Options Under Agreement Motor vehicles Vehicles [Member] Research and development Research and Development Expense [Member] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Accounts receivable Accounts Receivable, after Allowance for Credit Loss, Current Total lease payments Lessee, Operating Lease, Liability, to be Paid Other Deferred Tax Assets, Other Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale Common stock purchase price (in dollars per share) Shares Issued, Price Per Share Accumulated other comprehensive income (loss) AOCI, Debt Securities, Available-for-sale, Adjustment, after Tax Deferred income tax liabilities: Components of Deferred Tax Liabilities [Abstract] Gross Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Sale of Stock [Axis] Sale of Stock [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Basic and diluted weighted average number of common shares Weighted Average Number of Shares Outstanding, Basic and Diluted Net deferred income tax assets Deferred Tax Assets, Net of Valuation Allowance Laboratory and office equipment Laboratory and Office Equipment [Member] A facility that provides controlled conditions in which scientific or technological research, experiments, and measurement may be performed. and tangible personal property used in an office setting. Examples include, but are not limited to, computers, copiers and fax machine. Percent of fair market value to purchase shares Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Document Transition Report Document Transition Report Income Tax Examination [Table] Income Tax Examination [Table] Arrangements and Non-arrangement Transactions [Domain] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Prepaid expenditures Deferred Tax Liabilities, Prepaid Expenses Expected period of development Upfront Payment Recognition Period Refers to upfront payment recognition period. Significant Other Observable Inputs, Level 2 Fair Value, Inputs, Level 2 [Member] Provention PRV3279 Provention PRV3279 [Member] Provention PRV3279 Forfeited or expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Asset Class [Domain] Asset Class [Domain] General and administrative General and Administrative Expense [Member] Equity [Abstract] Total assets measured at fair value Assets, Fair Value Disclosure Stock options and RSUs Stock Options And Restricted Stock Units [Member] Stock Options And Restricted Stock Units Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Janssen Biotech Inc. Janssen Biotech Inc [Member] Counterparty in collaboration agreement Deferred revenue, current Contract with Customer, Liability, Current Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Cumulative Effect, Period of Adoption [Axis] Cumulative Effect, Period of Adoption [Axis] Customer Concentration Risk Customer Concentration Risk [Member] Vested and expected to vest (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Deferred income tax assets: Components of Deferred Tax Assets [Abstract] Summary of Fair Value Measurement Financial Assets Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Gross unrecognized tax benefits Unrecognized Tax Benefits that Would Impact Effective Tax Rate Expected term Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Number of operating segments Number of Operating Segments Entity File Number Entity File Number Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Weighted average lease term (in years) Operating Lease, Weighted Average Remaining Lease Term Stock plan related activity (in shares) Stock Issued During Period Shares Stock Plan Activity Number of shares issued due to stock plan related activity. Operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Orphan drug credit, net Deferred Tax Assets, Tax Credit Carryforwards, Other Stock-based compensation expense Share-based Payment Arrangement, Expense Beginning balance Ending balance Unrecognized Tax Benefits Counterparty Name [Axis] Counterparty Name [Axis] Common stock, $0.01 par value -- 125,000,000 shares authorized, 56,244,771 and 48,958,763 shares outstanding at December 31, 2020 and December 31, 2019, respectively Common Stock, Value, Issued Document Fiscal Year Focus Document Fiscal Year Focus Asset Purchase Agreement Asset Purchase Agreement [Member] Asset Acquisition Agreement Document Annual Report Document Annual Report Aggregate intrinsic value, Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Zai Lab Agreement Zai Labs Collaboration And License Agreement [Member] Zai Labs Collaboration And License Agreement Entity Current Reporting Status Entity Current Reporting Status Sale of common stock (in dollars per share) Sale of Stock, Price Per Share Retirement Benefits [Abstract] Purchases of marketable securities Payments to Acquire Debt Securities, Available-for-sale Net Loss Per Share Earnings Per Share, Policy [Policy Text Block] Common stock, shares issued (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Operating lease liabilities Lease liabilities Operating Lease, Liability Zai Lab Agreement, TRIDENT molecule Zai Labs Collaboration And License Agreement, TRIDENT molecule [Member] Zai Labs Collaboration And License Agreement, TRIDENT molecule Accounts receivable Increase (Decrease) in Accounts Receivable Total stockholders' equity Balance Balance Stockholders' Equity Attributable to Parent Concentration Risk Type [Domain] Concentration Risk Type [Domain] Total liabilities and stockholders' equity Liabilities and Equity Income Taxes Income Tax Disclosure [Text Block] Entity Address, City or Town Entity Address, City or Town Summary of Percentage of Customer Concentration Schedules of Concentration of Risk, by Risk Factor [Table Text Block] Basic and diluted net loss per common share (in usd per share) Income (Loss) from Continuing Operations, Per Basic and Diluted Share Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Restricted Stock Units Restricted Stock Units (RSUs) [Member] Operating lease cost Operating Lease, Cost 2024 Lessee, Operating Lease, Liability, to be Paid, Year Five General and administrative General and Administrative Expense Financial Instrument [Axis] Financial Instrument [Axis] Anti-dilutive stock options Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Provision for federal or state income taxes Current Income Tax Expense (Benefit) Net operating loss for limited use Operating Loss Carryforwards Limitations On Use Amount Amount of net operating loss carryforward, which are limited for use over the range of years. Increases for prior year tax positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Increases for current year tax positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Equity Component [Domain] Equity Component [Domain] Unrealized loss on investments OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Zai Lab Agreement, Margetuximab Zai Labs Collaboration And License Agreement, Margetuximab [Member] Zai Labs Collaboration And License Agreement, Margetuximab Valuation allowance Deferred Tax Assets, Valuation Allowance Property, equipment and software, net Property, equipment and software, net Property, Plant and Equipment, Net Entity Tax Identification Number Entity Tax Identification Number Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Stock-based Compensation Share-based Payment Arrangement [Text Block] Net loss Net loss Net Income (Loss) Attributable to Parent Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Debt Securities, Trading, and Equity Securities, FV-NI [Table] Debt Securities, Trading, and Equity Securities, FV-NI [Table] Leases [Abstract] Total current assets Assets, Current Current Fiscal Year End Date Current Fiscal Year End Date Components of the Company's Deferred Income Tax Assets (Liabilities) Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Percentage of common stock share outstanding Percentage Of Shares Of Companys Common Stock Outstanding For Increase In Shares Reserved For Issuance Under Stock Plan Percentage of shares of company's common stock outstanding for increase in shares reserved for issuance under stock plan. Document Fiscal Period Focus Document Fiscal Period Focus Maximum employee contribution percent Employee Stock Purchase Plan, Maximum Annual Contributions Per Employee, Percent Employee Stock Purchase Plan, Maximum Annual Contributions Per Employee, Percent Deferred revenue, noncurrent Contract with Customer, Liability, Noncurrent Janssen Collaboration And License Agreement Janssen Collaboration And License Agreement [Member] Janssen Collaboration And License Agreement Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Entity Filer Category Entity Filer Category Schedule of Stock-Based Compensation Expense Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Common Stock Common Stock [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Product and Service [Domain] Product and Service [Domain] Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] Discount rate Lessee, Operating Lease, Discount Rate Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Schedule of Property and Equipment Property, Plant and Equipment [Table Text Block] Zai Lab Zai Labs [Member] Zai Labs Additional development funding options Additional development funding options under agreement Additional funding available under agreement at counterparty's option U.S Treasury securities U.S. Treasury securities US Treasury Securities [Member] Issuance of common stock, net of offering costs (in shares) Number of shares issued or sold (in shares) Stock Issued During Period, Shares, New Issues Leasehold improvements Leasehold Improvements [Member] Sales revenue, net Revenue Benchmark [Member] Commercialization of molecules Number Of Molecules To Be Developed And Commercialized Under Agreement Number of molecules to be developed and commercialized as per collaboration. Money market funds Money Market Funds [Member] Less accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Aggregate intrinsic value, Vested and expected to vest Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Non-cash operating and investing activities: Noncash Investing and Financing Items [Abstract] Boehringer Ingelheim International GmbH Boehringer Ingelheim International GmbH [Member] Boehringer Ingelheim International GmbH Research and development credit, net Deferred Tax Assets, Tax Credit Carryforwards, Research Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Net change in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Provention PRV031 Provention PRV031 [Member] Provention PRV031 Zai Lab Collaboration And License Agreement Zai Lab Collaboration And License Agreement [Member] Zai Lab Collaboration And License Agreement Lessee, Operating Lease, Liability, Maturity Lessee, Operating Lease, Liability, Maturity [Table Text Block] Basis of Presentation and Principles of Consolidation Basis of Accounting, Policy [Policy Text Block] Costs and expenses: Costs and Expenses [Abstract] Servier DART Servier DART [Member] Represents agreement with Servier for DARTs Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Forfeited or expired (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Sale of Stock [Domain] Sale of Stock [Domain] I-Mab Biopharma Collaboration And License Agreement I-Mab Biopharma Collaboration And License Agreement [Member] I-Mab Biopharma Collaboration And License Agreement Plan Name [Domain] Plan Name [Domain] Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Tax Period [Domain] Tax Period [Domain] Organization and Nature of Operations Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Right-of-use assets modified in exchange for operating lease obligation Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Les Laboratoires Servier and Institut de Recherches Servier (Servier) Les Laboratoires Servier And Institut De Recherches Servier (Servier) [Member] Les Laboratoires Servier And Institut De Recherches Servier (Servier) Retirement of treasury stock Treasury Stock, Retired, Par Value Method, Amount Furniture and office equipment Furniture And Office Equipment [Member] Furniture and office equipment are movable furniture, fixtures, or other equipment that have no permanent connection to the structure of a building or utilities. These items depreciate substantially but definitely are important costs to consider when valuing a company, especially in liquidation. 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(Provention) Provention Bio [Member] Provention Bio Stock Incentive Plan 2013 Stock Incentive Plan 2013 [Member] Stock Incentive Plan 2013 [Member] Organization, Consolidation and Presentation of Financial Statements [Abstract] Lab equipment Equipment [Member] Current liabilities: Liabilities, Current [Abstract] Cash flows from financing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Entity Shell Company Entity Shell Company Vested and expected to vest (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Other permanent items Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount Recently Adopted and Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Entity Public Float Entity Public Float Statement of Financial Position [Abstract]