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Common stock issuance costs included in accrued liabilities General and Administrative Expense General and Administrative Expense [Member] General and administrative Lease liabilities Operating Lease, Liability Total operating lease liabilities Present value of lease liabilities Forecast Forecast [Member] Restricted Cash, Current Restricted cash - current assets Restricted cash Bristol-Myers Squibb Company. Bristol Myers Squibb Company [Member] Bristol Myers Squibb Company Bristol Myers Squibb Tranche two warrant. Tranche Two Warrant [Member] Tranche Two Warrant Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net income (loss) Lease Contractual Term [Domain] Collaboration and license agreement. Collaboration And License Agreement [Member] Collaboration and License Agreement Weighted Average Number of Shares Outstanding, Basic Weighted-average common shares outstanding used to calculate basic net income (loss) per share Weighted-average common shares outstanding used to calculate basic net income (loss) per share Shares used to compute net income (loss) per share, Basic Regeneron Regeneron Pharmaceuticals, Inc Regeneron Pharmaceuticals, Inc [Member] Regeneron Pharmaceuticals, Inc member. 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Document Period End Date Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV Statement of Financial Position [Abstract] RSUs Restricted Stock Units (RSUs) [Member] Lessee, Operating Lease, Existence of Option to Terminate [true false] Operating lease, existence of option to terminate Antidilutive Security, Excluded EPS Calculation [Table] Class of Stock [Axis] Class of Stock Warrants and Rights Outstanding, Maturity Date Expiration date Other Wholly Owned and Partnered Programs [Member] Other wholly owned and partnered programs. Other Wholly Owned and Partnered Programs Liabilities Total liabilities Sean A. McCarthy [Member] Sean A. McCarthy. Tenant Improvements Tenant improvement allowance Less: Tenant improvement allowance Deferred revenue recognition maturity year. Deferred Revenue Recognition Maturity Year Deferred Revenue Recognition Maturity Year Lessee, Operating Lease, Liability, to be Paid, Year Two 2027 Issuance cost Issuance cost Issuance cost Weighted Average Number of Shares Outstanding, Diluted Weighted-average common shares outstanding used to calculate diluted net income (loss) per share Shares used to compute net income (loss) per share, Diluted Weighted-average common shares outstanding used to calculate diluted net income (loss)per share Entity File Number External Costs External costs. Total external costs Amgen products. Amgen Products [Member] Amgen Products Proceeds from Sale, Maturity and Collection of Short-Term Investments, Total Proceeds from Sale, Maturity and Collection of Short-Term Investments Maturities of short-term investments Cover [Abstract] Prepaid Expense and Other Assets, Current Prepaid expenses and other current assets Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period PSU's cancelled Units cancelled Units forfeited Lease Obligation Incurred Right-of-use assets obtained in exchange for lease obligations. Lease rent expense Lease Rent Expense Lease rent expense. 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Right To Expand Number Of Additional Collaboration Target Right to expand the number of additional collaboration target Operating Lease, Liability, Current Operating lease liabilities - short term Current operating lease liabilities Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] Document Transition Report Operating Expenses Total operating expenses Accrued Liabilities, Current [Abstract] Research and Development Expense Research and development Research and development expenses Lessee, Operating Leases [Text Block] Leases Convertible Preferred Stock [Member] Convertible Preferred Stock Statement of Cash Flows [Abstract] Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract] Effect of potentially dilutive securities: Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Weighted Average Grant Date Fair Value Stock Issued During Period, Value, New Issues Stock issued during period, value, new issues Issuance of common stock in follow on offering, net of issuance cost Share-Based Payment Arrangement, Option, Activity [Table Text Block] Schedule of Activities Under Company's Stock Option Plans Cash paid for amounts included in the measurement of lease liabilities Cash Paid For Amounts Included In Measurement Of Lease Liabilities [Abstract] Cash paid for amounts included in measurement of lease liabilities. Performance based restricted stock units. Performance Based Restricted Stock Units [Member] Performance based RSUs Earnings Per Share [Text Block] Net Income (Loss) Per Share First Phase Two Study [Member] First phase two study. First Phase 2 Study Ending balance, shares Beginning balance, shares Shares, Issued Unrecognized Tax Benefits that Would Impact Effective Tax Rate Unrecognized tax benefits would affect company's effective tax rate Net income Net income (loss) Longitude Venture Partners V, L.P [Member] Longitude Venture Partners V, L.P. Longitude Venture Partners V, L.P Varseta-M (EpCAM) [Member] Varseta-M (EpCAM) VarsetaM (EpCAM). 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Lease commencement date Collaborative Arrangement and Arrangement Other than Collaborative [Table] Schedule Of Collaborative Arrangements And Noncollaborative Arrangement Transactions [Table] Underwritten Public Offering Underwritten Public Offering [Member] Underwritten public offering. Class of Warrant or Right [Line Items] Two Thousand Sixteen Operating Lease [Member] Two Thousand Sixteen Operating Lease Member 2016 Lease [Member] Weighted Average Number of Shares Issued, Basic Weighted-average common shares outstanding Weighted Average Number of Shares Issued, Basic, Total Other long-term liabilities Other Liabilities, Noncurrent Total transaction price Aggregate Collaboration Transaction Amount Aggregate collaboration transaction amount. Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Changes in operating assets and liabilities Immuno Gen Inc Immuno Gen Inc Immuno Gen Inc [Member] ImmunoGen, Inc. Letters of Credit Outstanding, Amount Letter of credit outstanding, amount Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Balances, end of the period Balances, beginning of the period Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Including Option Exercised, Total Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Including Option Exercised Proceeds from employee stock purchase plan and exercise of stock options Income Tax Disclosure [Abstract] Fair Value, Recurring and Nonrecurring [Table] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Additional Paid-in Capital [Member] Additional Paid-in Capital Statement of Income Location, Balance [Axis] Income Statement Location Trading Symbol Two Thousand Twenty Six Lease Operating Lease [Member] 2026 lease operating lease. 2026 Lease Operating Lease Employee-related Liabilities, Current, Total Employee-related Liabilities, Current Payroll and related expenses Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Cash flows from financing activities: Accounts Payable and Accrued Liabilities Disclosure [Text Block] Accrued Liabilities Earnings per share, basic and diluted EPS. Earnings Per Share, Basic and Diluted EPS [Abstract] Net income (loss) per share Lessee, Operating Lease, Liability, to be Paid Total lease payments Lessee, Operating Lease, Liability, Undiscounted Excess Amount Less imputed interest Equity Components [Axis] Equity Components Equity Component [Domain] Equity Component Asset Class [Axis] Issuance of common stock under the ESPP, shares Stock Issued During Period, Shares, Employee Stock Purchase Plans Statement of Comprehensive Income [Abstract] Future contingent milestone payment receivable. 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Non-Rule 10b51 Arrangement Modified Flag Proceeds from Collaborators Upfront payment received Finite-Lived Intangible Assets by Major Class [Axis] Clinical Development Milestone Payment Clinical development milestone payment Entity Registrant Name Other Nonoperating Income (Expense), Total Other Nonoperating Income (Expense) Other income (expense), net Other income Additional Paid in Capital, Ending Balance Additional Paid in Capital, Beginning Balance Additional Paid in Capital, Total Additional Paid in Capital Additional paid-in capital Upfront Consideration Estimated Research and Development Service Fees Upfront consideration estimated research and development service fees. Estimated research and development service fees Income Tax Expense (Benefit), Total Income Tax Expense (Benefit) Provision for income taxes Proceeds from Issuance of Common Stock Common stock, value of shares issued in connection with agreement Aggregate net proceeds Proceeds from issuance of common stock, net issuance cost Other Comprehensive Income (Loss), Tax [Abstract] Other comprehensive income (loss): Business Combination, Contingent Consideration, Type [Axis] Contingent Consideration by Type Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] ModernaTX, Inc [Member] Moderna ModernaTX, Inc ModernaTX, Inc [Member] Entity Common Stock, Shares Outstanding Accumulated Other Comprehensive Income (Loss), Net of Tax, Total Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income General Research and Development Expenses General research and development expenses. General research and development expenses Aggregate Fair Value Assets Fair Value Measurements Assets fair value measurements. Payments to Acquire Property, Plant, and Equipment, Total Payments to Acquire Property, Plant, and Equipment Purchases of property and equipment Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Granted Units awarded Assets Total assets PSU's Awarded, Grant date fair value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding Number of shares issued Sale of Stock, Number of Shares Issued in Transaction Stock Issued During Period, Shares, New Issues Issuance of common stock in follow on offering, net of issuance cost, shares Units vested Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period PSU's vested Units vested City Area Code Internal costs Internal Costs Internal costs. Restricted Cash and Cash Equivalents, Current, Total Restricted Cash and Cash Equivalent, Current Restricted cash New Lease Agreement Lease Agreements [Member] Counterparty Name [Domain] Counterparty Name Variable lease cost Variable Lease, Cost Stock Issued During Period, Value, Employee Stock Purchase Plan Issuance of common stock under the ESPP Operating Lease, Weighted Average Remaining Lease Term Operating lease Segment Reporting Information [Line Items] Performance Based Restricted Stock Units Two Thousand Twenty Four [Member] Performance Based Restricted Stock Units Twenty Twenty Four1 [Member] 2024 Performance based RSU Accrued liabilities and other long-term liabilities Increase Decrease In Accrued And Other Liabilities Noncurrent Increase decrease in accrued and other liabilities noncurrent. Lease expiration date Lease Expiration Date Letter of Credit Letter of Credit [Member] Property, Plant and Equipment, Net, Ending Balance Property, Plant and Equipment, Net, Beginning Balance Property, Plant and Equipment, Net, Total Property, Plant and Equipment, Net Property and equipment, net Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation Total Cash, cash equivalents and restricted cash, beginning of period Cash, cash equivalents and restricted cash, end of period Operating Income (Loss) Income from operations Income (loss) from operations Offering Expenses Offering expenses. Offering expenses Additions Contract with customer liability additions. Contract With Customer Liability Additions Retained Earnings [Member] Accumulated Deficit Business Combination, Contingent Consideration, Type [Domain] Contingent Consideration Type Share-Based Compensation Arrangements by Share-Based Payment Award, Restricted Stock Units, Vested and Expected to Vest [Table Text Block] Schedule of Company's TRSU Activities Share-based Payment Arrangement, Noncash Expense, Total Share-Based Payment Arrangement, Noncash Expense Stock-based compensation expense Underwriting discounts and commissions Payments of Stock Issuance Costs Operating Lease, Weighted Average Discount Rate, Percent Operating lease Operating Lease, Liability, Noncurrent Non-current operating lease liabilities Operating lease liabilities - long term Fair Value, Inputs, Level 1 [Member] Level I Class of Stock [Line Items] Disclosure Text Block [Abstract] Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Net cash provided by financing activities Summary of Company's Warrants Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block] Derivative Contract [Domain] Earnings Per Share Reconciliation [Abstract] Numerator: Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Summary of Potentially Dilutive Securities Excluded from Computation of Diluted Net Income (Loss) Per Share Entity Interactive Data Current Research and Development, Contract to Perform for Others [Table] Increase (Decrease) in Contract with Customer, Liability Deferred revenue Statement of Income Location, Balance [Domain] Income Statement Location Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Cash flows from operating activities: Accretion of discounts on short-term investments Accretion (Amortization) of Discounts and Premiums, Investments Contract with Customer, Asset, after Allowance for Credit Loss, Total Contract with Customer, Asset, after Allowance for Credit Loss Amount due from agreement Amount due from customer Annual License Maintenance Fee Annual license maintenance fee. Annual license maintenance fee Entity Tax Identification Number Clinical Development Milestones [Member] Clinical development milestones. Clinical development milestones Local Phone Number Number of targets selected. Number Of Targets Selected Number of targets selected Weighted Average Number of Shares Outstanding, Basic [Abstract] Basic Accounting Policies [Abstract] Revenue recognized Revenue from Contract with Customer, Excluding Assessed Tax, Total Revenues Total revenue Lessee, Operating Lease, Liability, to be Paid, Year Four 2029 Class of Stock [Domain] Class of Stock Accrued Professional Fees, Current Legal and professional expenses Stock, Class of Stock [Table] Entity Emerging Growth Company