Entity Central Index Key Document And Entity Information [Abstract] Document And Entity Information [Abstract] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Well Known Seasoned Issuer Entity Current Reporting Status Entity Current Reporting Status Entity Voluntary Filers Entity Voluntary Filers Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock Shares Outstanding Entity Public Float Entity Public Float Statement Of Financial Position [Abstract] ASSETS Assets [Abstract] Current Assets: Assets Current [Abstract] Cash and cash equivalents Cash And Cash Equivalents At Carrying Value Accounts receivable Accounts Receivable Net Current Prepaid expenses and other current assets Prepaid Expense And Other Assets Current Total current assets Assets Current Property and equipment, net Property Plant And Equipment Net Other assets Other Assets Noncurrent Total Assets Assets LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities And Stockholders Equity [Abstract] Current Liabilities: Liabilities Current [Abstract] Accounts payable Accounts Payable Current Accrued expenses Accrued Liabilities Current Current portion of deferred revenue Deferred Revenue Current Total current liabilities Liabilities Current Deferred revenue, net of current portion Deferred Revenue Noncurrent Other long-term liabilities Other Liabilities Noncurrent Commitments and contingencies (Note 6) Commitments And Contingencies Stockholders’ Equity: Stockholders Equity [Abstract] Common stock, $0.0001 par value; 120,000,000 shares authorized; 42,384,623 shares issued and outstanding and 36,018,540 shares issued and outstanding, respectively Common Stock Value Additional paid-in capital Additional Paid In Capital Common Stock Accumulated deficit Retained Earnings Accumulated Deficit Total stockholders’ equity Stockholders Equity Total Liabilities and Stockholders’ Equity Liabilities And Stockholders Equity Common stock, par value Common Stock Par Or Stated Value Per Share Common stock, shares authorized Common Stock Shares Authorized Common stock, shares issued Common Stock Shares Issued Common stock, shares outstanding Common Stock Shares Outstanding Income Statement [Abstract] Collaboration revenue License And Services Revenue Operating expenses: Costs And Expenses [Abstract] Research and development Research And Development Expense General and administrative General And Administrative Expense Total operating expenses Costs And Expenses Operating loss Operating Income Loss Interest income Investment Income Interest Loss before income taxes Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest Income tax benefit Income Tax Expense Benefit Net loss Net Income Loss Net loss per share, basic and diluted Earnings Per Share Basic And Diluted Weighted average shares outstanding, basic and diluted Weighted Average Number Of Share Outstanding Basic And Diluted The amount of collaboration consideration received that has been allocated to the value of equity units purchased by the collaboration partner. Effect of reorganization, shares. Effect of reorganization. Stock issued during period shares share-based compensation expense. Conversion of convertible preferred stock into common stock, shares. Conversion of convertible preferred stock into common stock. Statement Of Stockholders Equity [Abstract] Statement [Table] Statement [Table] Class of Stock Statement Class Of Stock [Axis] Class of Stock Class Of Stock [Domain] Series A-1, series A-2 and junior preferred. Series A-1, Series A-2 and Junior Preferred [Member] Series A One Series A Two And Junior Preferred [Member] Convertible Preferred Stock (Series B, Series A-2, Series A-1, Junior and Founder) [Member] Convertible Preferred Stock [Member] Equity Components Statement Equity Components [Axis] Equity Component Equity Component [Domain] Junior preferred units. Junior Preferred Units [Member] Junior Preferred Units [Member] Common units. Common Units [Member] Common Units [Member] Common Stock [Member] Common Stock [Member] Incentive units. Incentive [Member] Incentive Units [Member] Additional Paid-In Capital [Member] Additional Paid In Capital [Member] Accumulated Deficit [Member] Retained Earnings [Member] Related Party Related Party Transactions By Related Party [Axis] Related Party Related Party [Domain] Novartis Institutes for BioMedical Research Inc. Novartis [Member] Novartis Institutes For Bio Medical Research Inc [Member] Type of Arrangement and Non-arrangement Transactions Type Of Arrangement [Axis] Arrangements and Non-arrangement Transactions Arrangements And Nonarrangement Transactions [Member] Collaborative Arrangement [Member] Collaborative Arrangement [Member] Class A-2 preferred units. Class A-2 Preferred Units [Member] Class A2 Preferred Units [Member] Series B Preferred Stock [Member] Series B Preferred Stock [Member] Statement [Line Items] Statement [Line Items] Beginning balance Temporary Equity Carrying Amount Attributable To Parent Beginning balance Beginning balance, shares Beginning balance, shares Temporary Equity Shares Outstanding Conversion of convertible preferred stock Conversion Of Convertible Preferred Stock Into Common Stock Conversion of convertible preferred stock, shares Conversion Of Convertible Preferred Stock Into Common Stock Shares Issuance of units/stock Stock Issued During Period Value New Issues Issuance of units/stock, shares Stock Issued During Period Shares New Issues Allocation from Novartis collaboration to carrying value of Preferred Shares Collaboration Consideration Allocated To Equity Tax provision associated with intraperiod tax allocation Income Tax Expense Benefit Intraperiod Tax Allocation Effect of Reorganization Effect Of Reorganization Effect of Reorganization, shares Effect Of Reorganization Shares Issuance of Series B Preferred Shares, net of issuance costs Temporary Equity Stock Issued During Period Value New Issues Temporary equity stock issued during period shares new issues. Issuance of Series B Preferred Shares, net of issuance costs, shares Temporary Equity Stock Issued During Period Shares New Issues Exercise of stock options Stock Issued During Period Value Stock Options Exercised Exercise of stock options, shares Stock Issued During Period Shares Stock Options Exercised Issuance of shares under employee stock purchase plan Stock Issued During Period Value Employee Stock Purchase Plan Issuance of shares under employee stock purchase plan, shares Stock Issued During Period Shares Employee Stock Purchase Plans Equity-based compensation Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value Equity-based compensation, shares Stock Issued During Period Shares Sharebased Compensation Expense Net loss Ending balance Ending balance Ending balance, shares Ending balance, shares Units/stock issuance cost Adjustments To Additional Paid In Capital Stock Issued Issuance Costs Payments of temporary equity issuance costs. Future cash outflow to pay the remaining obligation for in-process research and development assets acquired. Future cash outflow to pay costs incurred related to the entity's initial public offering. Statement Of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided By Used In Operating Activities Continuing Operations [Abstract] Adjustments to reconcile net loss to net cash (used in) provided by operating activities: Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Depreciation and amortization Depreciation Depletion And Amortization Loss on disposal of property and equipment Gain Loss On Sale Of Property Plant Equipment Equity-based compensation Share Based Compensation Changes in operating assets and liabilities: Increase Decrease In Operating Capital [Abstract] Accounts receivable Increase Decrease In Accounts Receivable Prepaid expenses and other current assets Increase Decrease In Prepaid Deferred Expense And Other Assets Accounts payable Increase Decrease In Accounts Payable Accrued expenses Increase Decrease In Accrued Liabilities Deferred revenue Increase Decrease In Deferred Revenue Other assets Increase Decrease In Other Operating Assets Other long-term liabilities Increase Decrease In Other Noncurrent Liabilities Net cash (used in) provided by operating activities Net Cash Provided By Used In Operating Activities Continuing Operations CASH FLOWS FROM INVESTING ACTIVITIES: Net Cash Provided By Used In Investing Activities Continuing Operations [Abstract] Purchases of property and equipment Payments To Acquire Property Plant And Equipment Net cash used in investing activities Net Cash Provided By Used In Investing Activities Continuing Operations CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided By Used In Financing Activities Continuing Operations [Abstract] Proceeds from sale of Class A-1 and A-2 preferred units and Series B preferred stock Proceeds From Issuance Of Convertible Preferred Stock Payments to acquire in-process research and development Payments To Acquire In Process Research And Development Payment of preferred unit and preferred stock issuance costs Payments Of Temporary Equity Issuance Costs Proceeds from common stock offering Proceeds From Issuance Of Common Stock Proceeds from options exercised Proceeds From Stock Options Exercised Issuance of shares through employee stock purchase plan Proceeds From Stock Plans Payment of common stock offering costs Payments Of Stock Issuance Costs Net cash provided by financing activities Net Cash Provided By Used In Financing Activities Continuing Operations Net increase in cash and cash equivalents Cash And Cash Equivalents Period Increase Decrease Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION: Supplemental Cash Flow Information [Abstract] Purchases of property and equipment unpaid at period end Capital Expenditures Incurred But Not Yet Paid Acquisition of in-process research and development unpaid at period end In Process Research And Development Acquired But Not Yet Paid Financing costs incurred but unpaid at period end Initial Public Offering Costs Incurred But Not Yet Paid Conversion of convertible preferred stock to common stock Conversion Of Stock Amount Converted1 Organization Consolidation And Presentation Of Financial Statements [Abstract] The Company Organization Consolidation And Presentation Of Financial Statements Disclosure [Text Block] Accounting Policies [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Property Plant And Equipment [Abstract] Property and Equipment, Net Property Plant And Equipment Disclosure [Text Block] Payables And Accruals [Abstract] Accrued Expenses Accounts Payable And Accrued Liabilities Disclosure [Text Block] Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Commitments And Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments And Contingencies Disclosure [Text Block] Collaborations Collaborative Arrangement Disclosure [Text Block] Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] Equity-Based Compensation Disclosure Of Compensation Related Costs Share Based Payments [Text Block] Earnings Per Share [Abstract] Loss Per Share Earnings Per Share [Text Block] Equity [Abstract] Stockholders’ Equity Stockholders Equity Note Disclosure [Text Block] Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Quarterly Financial Information Disclosure [Abstract] Unaudited Quarterly Results Quarterly Financial Information [Text Block] Basis of Presentation Basis Of Accounting Policy Policy [Text Block] Use of Estimates Use Of Estimates Fair Value Measurements Fair Value Measurement Policy Policy [Text Block] Cash Equivalents Cash And Cash Equivalents Policy [Text Block] Concentrations of Credit Risk Concentration Risk Credit Risk Property and Equipment Property Plant And Equipment Policy [Text Block] Impairment of Long-Lived Assets Impairment Or Disposal Of Long Lived Assets Policy [Text Block] Income Taxes Income Tax Policy [Text Block] Revenue Recognition Revenue Recognition Policy [Text Block] Research and Development Expenses Research And Development Expense Policy Equity-Based Compensation Compensation Related Costs Policy [Text Block] (Loss) Earnings per Share Earnings Per Share Policy [Text Block] Segment Information Segment Reporting Policy Policy [Text Block] Recent Accounting Pronouncements New Accounting Pronouncements Policy Policy [Text Block] Summary of Financial Assets Recognized at Fair Value Fair Value Assets Measured On Recurring Basis [Text Block] Property plant and equipments estimated useful lives. Summary of Property and Equipment at Cost and Recognizes Depreciation and Amortization Using the Straight-Line Method Over Estimated Useful Lives Property Plant And Equipments Estimated Useful Lives Table [Text Block] Schedule of Property and Equipment Property Plant And Equipment [Text Block] Schedule of Accrued Expenses Schedule Of Accrued Liabilities Table [Text Block] Schedule of Reconciliation of the Federal Statutory Income Tax Rate and the Company's Effective Income Tax Rate Schedule Of Effective Income Tax Rate Reconciliation Table [Text Block] Summary of Company's Net Deferred Tax Assets (Liabilities) Schedule Of Deferred Tax Assets And Liabilities Table [Text Block] Schedule of Future Minimum Lease Payments Schedule Of Future Minimum Rental Payments For Operating Leases Table [Text Block] Schedule of Equity-Based Compensation Expense Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Text Block] Summary of Restricted Stock Activity, Including Converted Founder Stock Schedule Of Share Based Compensation Restricted Stock Units Award Activity Table [Text Block] Summary of Weighted Average Assumptions Used to Compute Fair Value of Option Granted Schedule Of Share Based Payment Award Stock Options Valuation Assumptions Table [Text Block] Summary of Stock Option Activity Schedule Of Share Based Compensation Stock Options Activity Table [Text Block] Schedule of Basic and Diluted Net Loss Per Share Schedule Of Earnings Per Share Basic And Diluted Table [Text Block] Potential Dilutive Securities Excluded from Computation of Diluted Net Loss Per Common Share Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Text Block] Schedule of Results of Operations on Quarterly Basis Schedule Of Quarterly Financial Information Table [Text Block] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Abstract] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value, Hierarchy Fair Value By Fair Value Hierarchy Level [Axis] Fair Value Hierarchy Fair Value Measurements Fair Value Hierarchy [Domain] Level 1 [Member] Fair Value Inputs Level1 [Member] Level 2 [Member] Fair Value Inputs Level2 [Member] Level 3 [Member] Fair Value Inputs Level3 [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] Cash equivalents Cash And Cash Equivalents Fair Value Disclosure Total Assets Fair Value Disclosure Property Plant and Equipment Useful Life and Values [Abstract] Property Plant And Equipment Useful Life And Values [Abstract] Schedule Of Property Plant And Equipment [Table] Schedule Of Property Plant And Equipment [Table] Property, Plant and Equipment, Type Property Plant And Equipment By Type [Axis] Property, Plant and Equipment, Type Property Plant And Equipment Type [Domain] Laboratory equipment. Laboratory Equipment [Member] Laboratory Equipment [Member] Office furniture and equipment. Office Furniture and Equipment [Member] Office Furniture And Equipment [Member] Computer Software [Member] Software And Software Development Costs [Member] Computer Equipment [Member] Computer Equipment [Member] Leasehold Improvements [Member] Leasehold Improvements [Member] Property, Plant and Equipment [Line Items] Property Plant And Equipment [Line Items] Estimated useful life Property Plant And Equipment Useful Life Estimated useful life Property Plant And Equipment Estimated Useful Lives Percentage of likelihood of realization needed in order for the company to record a tax benefit. Summary Of Significant Accounting Policies [Line Items] Summary Of Significant Accounting Policies [Table] Summary Of Significant Accounting Policies [Table] Summary Of Significant Accounting Policies [Table] Adjustments for New Accounting Pronouncements Adjustments For New Accounting Pronouncements [Axis] Type of Adoption Type Of Adoption [Member] Accounting Standards Update 2014-09 [Member] Accounting Standards Update201409 [Member] Initial Application Period Cumulative Effect Transition Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition Initial Application Period Cumulative Effect Transition [Domain] Difference between Revenue Guidance in Effect after Topic 606 Difference Between Revenue Guidance In Effect Before And After Topic606 [Member] Summary Of Significant Accounting Policies [Line Items] Summary Of Significant Accounting Policies [Line Items] Percentage of likelihood of realization required to record tax benefit Percentage Likelihood Of Realization Required To Record Tax Benefit Loss to participating securities Participating Securities Distributed And Undistributed Earnings Loss Diluted Contractual obligation Contractual Obligation Number of reportable segment Number Of Reportable Segments Recognition of additional revenue New Accounting Pronouncement Or Change In Accounting Principle Cumulative Effect Of Change On Equity Or Net Assets1 Computer Software [Member] Software Development [Member] Property and equipment Property Plant And Equipment Gross Less: accumulated depreciation and amortization Accumulated Depreciation Depletion And Amortization Property Plant And Equipment Property and equipment, net Depreciation and amortization expense Depreciation Employee compensation and benefits Employee Related Liabilities Current Research and development and professional expenses Accrued Professional Fees Current Accrued expenses Collaboration agreement consideration amount. Income Tax Benefit [Line Items] Income Tax Benefit [Table] Income Tax Benefit [Table] Income Tax Benefit [Table] Counterparty Name Counterparty Name [Axis] Counterparty Name Repurchase Agreement Counterparty Name [Domain] Income Tax Authority Income Tax Authority [Axis] Income Tax Authority Income Tax Authority [Domain] Federal [Member] Domestic Country [Member] State [Member] State And Local Jurisdiction [Member] Scenario Statement Scenario [Axis] Scenario, Unspecified Scenario Unspecified [Domain] Scenario, Plan [Member] Scenario Plan [Member] Range Range [Axis] Range Range [Member] Maximum [Member] Maximum [Member] Minimum [Member] Minimum [Member] Income Tax Benefit [Line Items] Income Tax Benefit [Line Items] Consideration received under collaboration agreement Total fixed amount of consideration under collaboration agreement Collaboration Agreement Consideration Amount Income tax provision within equity Income Tax Effects Allocated Directly To Equity Income tax provision Effective income tax rate reconciliation intraperiod tax allocation. Effective income tax rate reconciliation permanent items. Federal statutory income tax rate Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate State income taxes Effective Income Tax Rate Reconciliation State And Local Income Taxes Intraperiod tax allocation Effective Income Tax Rate Reconciliation Intraperiod Tax Allocation Permanent items Effective Income Tax Rate Reconciliation Permanent Items Research and development tax credits Effective Income Tax Rate Reconciliation Tax Credits Research Stock-based compensation Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost Change in U.S. tax rate Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate Change in valuation allowance Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance Effective income tax rate Effective Income Tax Rate Continuing Operations Deferred tax assets, deferred expense, capitalized start-up. Deferred tax assets: Deferred Tax Assets Net [Abstract] Intangibles, including acquired in-process research and development Deferred Tax Assets In Process Research And Development Capitalized start-up costs Deferred Tax Assets Deferred Expense Capitalized Startup Net operating loss carryforwards Deferred Tax Assets Operating Loss Carryforwards Research and development credit carryforwards Deferred Tax Assets Tax Credit Carryforwards Research Deferred revenue Deferred Tax Assets Deferred Income Equity-based compensation Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost Accruals and allowances Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts Gross deferred tax assets Deferred Tax Assets Gross Deferred tax asset valuation allowance Deferred Tax Assets Valuation Allowance Total deferred tax assets Deferred Tax Assets Net Deferred tax liabilities: Deferred Tax Liabilities Net [Abstract] Fixed assets Deferred Tax Liabilities Property Plant And Equipment Total deferred tax liabilities Deferred Income Tax Liabilities Net deferred tax asset (liability) Deferred Tax Assets Liabilities Net Deferred tax assets operating loss carryforwards expiration year. Deferred tax assets tax credit carryforwards research expiration year. Deferred tax assets, operating loss carryforwards, expiration description. Deferred tax assets, tax credit carryforwards, research, expiration description. Net operating loss carryforwards, federal Deferred Tax Assets Operating Loss Carryforwards Domestic Net operating loss carryforwards, state Deferred Tax Assets Operating Loss Carryforwards State And Local Net operating loss carryforwards, expiration year Deferred Tax Assets Operating Loss Carryforwards Expiration Year Net operating loss carryforwards, expiration date description Deferred Tax Assets Operating Loss Carryforwards Expiration Description Research and development tax credit Research and development tax credits, expiration year Deferred Tax Assets Tax Credit Carryforwards Research Expiration Year Research and development tax credits, expiration date description Deferred Tax Assets Tax Credit Carryforwards Research Expiration Description Increase in deferred tax assets valuation allowance. Increase in valuation allowance Increase In Deferred Tax Assets Valuation Allowance Unrecognized tax benefits Unrecognized Tax Benefits Tax cuts and jobs act of 2017 incomplete accounting change in tax rate deferred tax asset provisional income tax benefit. Tax cuts and jobs act of 2017 measurement period. U.S. corporate income tax rate Provisional amount for decrease in net deferred tax assets offset by decrease in valuation allowance due to remeasurement Tax Cuts And Jobs Act Of2017 Incomplete Accounting Change In Tax Rate Deferred Tax Asset Provisional Income Tax Benefit Measurement period Tax Cuts And Jobs Act Of2017 Measurement Period Number of years that an operating lease may be extended. Term of lease period before optional termination. Schedule Of Operating Leased Assets [Table] Schedule Of Operating Leased Assets [Table] Lease Arrangement, Type Lease Arrangement Type [Axis] Lease Arrangement, Type Lease Arrangement Type [Domain] Property leases. Property Leases [Member] Property Leases [Member] Geographical Statement Geographical [Axis] Geographical Segment Geographical [Domain] Cambridge, Massachusetts [Member] Cambridge, Massachusetts [Member] Cambridge Massachusetts [Member] Caribou. Caribou [Member] Caribou [Member] Research and Development Arrangement, Contract to Perform for Others, Type Research And Development Arrangement Contract To Perform For Others By Type [Axis] Research and Development Arrangement, Contract to Perform for Others, Type Research And Development Arrangement Contract To Perform For Others Type [Domain] Development and regulatory milestones Development And Regulatory Milestones [Member] Development And Regulatory Milestones [Member] Sales based milestones. Sales Based Milestones [Member] Sales Based Milestones [Member] Operating Leased Assets [Line Items] Operating Leased Assets [Line Items] Operating lease security deposit Security Deposit Capital lease obligation additional period of term of leases in years Lessee Leasing Arrangement Operating Leases Optional Extension Period Operating lease arrangement term Lessee Leasing Arrangements Operating Leases Term Of Contract Number of lease years before optional extension and early termination can be exercised Number Of Lease Period Before Optional Termination Prepaid lease payments Prepaid Expense Current And Noncurrent Rent expense Operating Leases Rent Expense Net Operating Leases Future Minimum Payments Due [Abstract] 2018 Operating Leases Future Minimum Payments Due Current 2019 Operating Leases Future Minimum Payments Due In Two Years 2020 Operating Leases Future Minimum Payments Due In Three Years 2021 Operating Leases Future Minimum Payments Due In Four Years 2022 Operating Leases Future Minimum Payments Due In Five Years Thereafter Operating Leases Future Minimum Payments Due Thereafter Total future minimum lease payments Operating Leases Future Minimum Payments Due Milestone potential payments. The related party's percentage of fully diluted equity participation in the entity. Percentage of shares owned Related Party Ownership Percentage Milestone payments Milestone Potential Payments Additional technology access fees to which the company is entitled to receive. Amount of quarterly research payment to which the Company is entitled to receive under the collaboration. The aggregate amount of research payments the Company is entitled to received under the collaboration. Collaboration arrangement term of agreement. Aggregate potential clinical development milestone payments available to be earned under a collaboration arrangement for each available target selected by the collaborator. Aggregate potential regulatory milestone payments available to be earned under a collaboration arrangement for a product candidate's first indication. Aggregate potential regulatory milestone payments available to be earned under a collaboration arrangement for a product candidate's second indication. Aggregate potential sales-based milestone payments available to be earned under a collaboration arrangement. Estimated fair value of preferred stock. Schedule Of Collaborative Arrangements And Noncollaborative Arrangement Transactions [Table] Schedule Of Collaborative Arrangements And Noncollaborative Arrangement Transactions [Table] Class A Preferred units. Class A Preferred Units [Member] Class A Preferred Units [Member] Regeneron Pharmaceuticals Inc. Regeneron Pharmaceuticals Inc. [Member] Regeneron Pharmaceuticals Inc [Member] Deferred Revenue Arrangement Type Deferred Revenue Arrangement Type [Axis] Deferred Revenue Deferred Revenue Arrangement Type [Domain] Research and development services. Research and Development Services [Member] Research And Development Services [Member] Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] Deferred Revenue Additions Deferred Revenue Additions Technology access fees Technology Access Fees Quarterly research payments Quarterly Research Payments Total research funding Research Funding Aggregate Amount Research term Collaboration Arrangement Term Of Agreement Development based milestone payments under agreement Development Based Milestone Payments Under Agreement Regulatory based milestone payments for first indication Regulatory Based Milestone Payments Under Collaboration First Indication Regulatory based milestone payments for second indication Regulatory Based Milestone Payments Under Collaboration Second Indication Sales based milestone payments under agreement Sales Based Milestone Payments Under Agreement Proceeds from issuance of preferred stock Proceeds From Issuance Of Preferred Stock And Preference Stock Estimated fair value of units Estimated Fair Value Of Preferred Stock Difference between cash proceeds received and estimated fair value of preferred units Accounts receivable Accounts Receivable Related Parties Deferred revenue Deferred Revenue Aggregate potential regulatory milestone payments available to be earned under a collaboration arrangement. Represents the percentage of obligated fund on research and development costs under collaboration agreement. Purchase of common stock through private placement Proceeds From Issuance Of Private Placement Regulatory based milestone payments under agreement Regulatory Based Milestone Payments Under Agreement Percentage of obligated fund on research and development costs Collaborative Arrangement Obligation To Fund Percentage The number of units of accounting identified in a multiple element arrangement. Amount allocated to licenses to targets and associated research activities and evaluation plans. Amount allocated to technology collaboration. Licenses to targets and associated research activities and evaluation plans performance period. Describes the allocation of consideration to a specific unit of accounting at the inception of a multiple-deliverable arrangement Revenue Recognition, Multiple-deliverable Arrangements, Allocation to Specific Unit of Accounting Revenue Recognition Multiple Deliverable Arrangements Allocation To Specific Unit Of Accounting Number of accounting based units Revenue Recognition Multiple Deliverable Arrangements Number Of Units Of Accounting Amount allocated to licenses to targets and associated research activities and evaluation plans Amount Allocated To Licenses To Targets And Associated Research Activities And Evaluation Plans Amount allocated to technology collaboration Amount Allocated To Technology Collaboration Licenses to targets and associated research activities and evaluation plans performance period Licenses To Targets And Associated Research Activities And Evaluation Plans Performance Period Accounts receivable Accounts Receivable Net Amount of one time payment the entity could receive if the collaboration partner elected to extend the collaboration arrangement. The period by which the collaboration arrangement may be extended. The period under which the Company may have royalty obligations to a collaboration partner following the termination of the collaboration agreement. Notice period under which the collaboration may be terminated by the entity's partner. One time collaboration payment One Time Payment To Extend Collaboration Arrangement Collaboration term extension period Collaboration Agreement Extension Period Royalty payment obligation expiration period Royalty Payment Obligations Expiration Period Termination period of agreement Termination Of Agreement Notice Period Compensation Related Costs [Abstract] Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Table] Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Table] Income Statement Location Income Statement Location [Axis] Income Statement Location Income Statement Location [Domain] Research and Development [Member] Research And Development Expense [Member] General and Administrative [Member] General And Administrative Expense [Member] Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] Equity-based compensation expense Allocated Share Based Compensation Expense Number of Shares, Unvested, Beginning balance Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number Number of Shares, Vested Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Number of Shares, Forfeited Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period Number of Shares, Unvested, Ending balance Weighted Average Grant Date Fair Value per Share, Unvested, Beginning balance Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Weighted Average Grant Date Fair Value Weighted Average Grant Date Fair Value per Share, Vested Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Weighted Average Grant Date Fair Value Weighted Average Grant Date Fair Value per Share, Forfeited Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Weighted Average Grant Date Fair Value Weighted Average Grant Date Fair Value per Share, Unvested, Ending balance Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Award Type Award Type [Axis] Equity Award Share Based Compensation Arrangements By Share Based Payment Award Award Type And Plan Name [Domain] Restricted Stock [Member] Restricted Stock [Member] Stock Options [Member] Employee Stock Option [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Total unrecognized stock-based compensation expense Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Share Based Awards Other Than Options Weighted average period of unrecognized compensation costs Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 Weighted average grant date fair value per share Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value Risk-free interest rate Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Expected life of options Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 Expected volatility of underlying stock Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate Expected dividend yield Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate Number of Options, Outstanding, Beginning Balance Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Number of options, Granted Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross Number of options, Exercised Number of options, Forfeited Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period Number of Options, Outstanding, Ending Balance Number of Options, Exercisable Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Weighted Average Exercise Price per Share, Outstanding, Beginning Balance Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price Weighted Average Exercise Price per Share, Granted Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price Weighted Average Exercise Price per Share, Exercised Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price Weighted Average Exercise Price per Share, Forfeited Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price Weighted Average Exercise Price per Share, Outstanding, Ending Balance Weighted Average Exercise Price per Share, Exercisable Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price Weighted Average Remaining Contractual Term, Outstanding Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 Weighted Average Remaining Contractual Term, Exercisable Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 Aggregate Intrinsic Value, Outstanding Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value Aggregate Intrinsic Value, Exercisable Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 Unrecognized compensation cost related to stock options Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options Net loss per share attributable to common stockholders, basic and diluted Earnings loss per share. Earnings Loss Per Share [Table] Earnings Loss Per Share [Table] Earnings Loss Per Share [Table] Sale of Stock Subsidiary Sale Of Stock [Axis] Sale of Stock Sale Of Stock Name Of Transaction [Domain] IPO [Member] I P O [Member] Private Placement [Member] Private Placement [Member] Public offering. Public Offering [Member] Public Offering [Member] Underwriting agreement. Underwriting Agreement [Member] Underwriting Agreement [Member] Earnings Loss Per Share [Line Items] Earnings Loss Per Share [Line Items] Number of common stock issued upon conversion of shares Conversion of convertible preferred stock into common stock Convertible Preferred Stock Shares Issued Upon Conversion Common stock par value per share Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Antidilutive Securities Antidilutive Securities Excluded From Computation Of Earnings Per Share By Antidilutive Securities [Axis] Antidilutive Securities, Name Antidilutive Securities Name [Domain] Unvested Restricted Stock [Member] Restricted Stock Units R S U [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] Potential dilutive securities excluded from computation of diluted net loss per common share Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount Effective date of reverse stock split. Schedule Of Stock By Class [Table] Schedule Of Stock By Class [Table] Class Of Stock [Line Items] Class Of Stock [Line Items] Common stock price per share Shares Issued Price Per Share Proceeds from issuance initial public offering Proceeds From Issuance Initial Public Offering Reverse stock split ratio of common stock Stockholders Equity Note Stock Split Conversion Ratio1 Reverse stock split description Stockholders Equity Reverse Stock Split Effective date of reverse stock split Effective Date Of Reverse Stock Split Convertible preferred stock conversion ratio Convertible Preferred Stock Terms Of Conversion Number of common stock issued upon conversion of value Proceeds from common stock offering Accretion of redeemable preferred stock. Accretion amount recognized Accretion Of Redeemable Preferred Stock The entity's obligation to fund intellectual property costs of the related party. Schedule Of Related Party Transactions By Related Party [Table] Schedule Of Related Party Transactions By Related Party [Table] Class A-1 preferred units. Class A-1 Preferred Units [Member] Class A1 Preferred Units [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Junior preferred units issued Preferred Units Issued Percentage of related party obligation Related Party Commitment Obligation Percentage Research and development expense related to license and service agreements with related party Current obligations related to license and service agreements with related party Due To Related Parties Current General and administrative expenses Preferred stock, shares acquired Preferred Stock Shares Issued Common stock, shares acquired Accounts receivable Accounts Receivable Related Parties Current Quarterly Financial Data [Abstract] Operating loss