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Type of Revenue [Extensible List] Revenue, Product and Service [Extensible Enumeration] Credit Facility [Domain] Equity [Abstract] Units awarded Granted Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Options exercised Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Entity Incorporation, State or Country Code Equity Components Equity Components [Axis] Accounts receivable Increase (Decrease) in Accounts Receivable Restructuring and Related Activities [Abstract] Research and clinical expenses Accrued Research And Clinical Current Accrued research and clinical current. Contract Termination [Member] Contract Termination Cost Units vested PSU's vested Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Local Phone Number Sale of Stock [Axis] Options exercisable, end of the period Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price Milestone payment received Milestone Payments Received From Revenue Recognized During Period Milestone payments received from revenue recognized during period. Milestone payment received Pre clinical candidate. Pre Clinical Candidate [Member] Pre Clinical Candidate Goodwill Goodwill Goodwill, Total Goodwill, Beginning Balance Goodwill, Ending Balance Number of oncology target Number Of Oncology Target Number of oncology target. Statement of Cash Flows [Abstract] Target selection fees. 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Schedule of Activities for Company's PSUs Share-Based Compensation Arrangements by Share-Based Payment Award, Performance-Based Units, Vested and Expected to Vest [Table Text Block] Units Awarded PSU's awarded Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Proceeds from exercise of stock options Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Including Option Exercised Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Including Option Exercised, Total Security Exchange Name Times of increments for extended collaboration target research time Increments Of Extended Collaboration Target Research Times Increments of extended collaboration target research times. Recently Issued Accounting Standards Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Timing of Transfer of Good or Service [Axis] Option forfeited/expired Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Diluted Weighted Average Number of Shares Outstanding, Diluted [Abstract] Entity Emerging Growth Company Amendment Flag Schedule of Accrued Liabilities Schedule of Accrued Liabilities [Table Text Block] Investments, Gross Unrealized Losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Accounting Standards Update [Domain] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Beginning balance, shares Ending balance, shares Shares, Issued Restructuring and Related Activities Disclosure [Text Block] Restructuring Total transaction price Aggregate Collaboration Transaction Amount Aggregate collaboration transaction amount. ImmunoGen, Inc. Immuno Gen Inc [Member] Immuno Gen Inc Immuno Gen Inc Leases [Abstract] Entity File Number Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Share-Based Payment Arrangement [Abstract] Net income (loss) per share Earnings Per Share, Basic and Diluted EPS [Abstract] Earnings per share, basic and diluted EPS. Accounts payable Accounts Payable, Current Accounts Payable, Current, Total Balance at March 31, 2024 Balance at December 31, 2023 Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Total operating expenses Operating Expenses License payment term License Payment Term License payment term. Collaborative Arrangement Collaborative Arrangement [Member] Entity Address, Address Line Two Preferred Stock, Value, Issued Preferred Stock, Value, Issued, Total Preferred Stock, Value, Issued, Beginning Balance Preferred Stock, Value, Issued, Ending Balance Convertible preferred stock Entity Small Business Entity Shell Company Exercise price of warrants Class of Warrant or Right, Exercise Price of Warrants or Rights Class of Warrant or Right [Domain] Net Income (Loss) Per Share Earnings Per Share [Text Block] Entity Address, Address Line One Contingent milestone payments receivable Contingent Milestone Payments Receivable Future contingent milestone payment receivable. Lessee operating leases future minimum payments due future minimum sublease rentals due in year three. Lessee Operating Leases Future Minimum Payments Due Future Minimum Sublease Rentals Due In Year Three 2026 Antidilutive Securities [Axis] Payment of upfront fees Payment Of Upfront Fees Payment of upfront fees. Name of plaintiff Loss Contingency, Name of Plaintiff Subsequent Event Type [Domain] Income Statement Location Income Statement Location [Axis] Third And Fourth Immuno-Oncology Targets Third And Fourth Targets [Member] Third and fourth targets. Third And Fourth Target Non-Rule 10b51 Arrangement Modified Flag Non Rule 10b51 Arr Modified Flag Non Rule 10b51 arrangement modified flag. Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total Level II Fair Value, Inputs, Level 2 [Member] Common stock, shares issuable under agreement, price per share Share Price Schedule Of Collaborative Arrangements And Noncollaborative Arrangement Transactions [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Product and Service Product and Service [Axis] Deferred revenue, net of current portion Contract with Customer, Liability, Noncurrent Title of 12(b) Security Tranche two member. Tranche Two [Member] Tranche Two Accounting Standards Update [Axis] Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] ModernaTX, Inc [Member] ModernaTX, Inc [Member] ModernaTX, Inc Moderna Subsequent Event [Table] Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Cash, Cash Equivalents and Restricted Cash Contingent Consideration by Type Contingent Consideration by Type [Axis] Deferred revenue Contract with Customer, Liability Contract with Customer, Liability, Total Beginning Balance Ending Balance Schedule of Company's TRSU Activities Share-Based Compensation Arrangements by Share-Based Payment Award, Restricted Stock Units, Vested and Expected to Vest [Table Text Block] Stock-Based Compensation Share-Based Payment Arrangement [Text Block] Units cancelled PSU's cancelled Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Restructuring Costs, Total Restructuring Costs RestructuringCosts Lessee operating leases future minimum payments due future minimum sublease rentals due in next twelve months. Lessee Operating Leases Future Minimum Payments Due Future Minimum Sublease Rentals Due In Next Twelve Months 2024 Income Statement Location Income Statement Location [Domain] Options granted Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Restricted cash Restricted Cash and Cash Equivalents, Current Restricted Cash and Cash Equivalents, Current, Total Document Type Net cash provided by (used in) investing activities Net Cash Provided by (Used in) Investing Activities Document Quarterly Report Share-Based Payment Arrangement [Member] Stock Compensation Plan Sublicense Agreement Sublicense Agreement [Member] Sublicense agreement. Counterparty Name Counterparty Name [Domain] Number of collaboration agreements Number Of Collaboration Agreements Number of collaboration agreements. Lessee operating leases future minimum payments due future minimum sublease rentals due in year two. Lessee Operating Leases Future Minimum Payments Due Future Minimum Sublease Rentals Due In Year Two 2025 Units cancelled PSU's cancelled Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period units cancelled Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities 2024 Performance based RSU Performance Based Restricted Stock Units Twenty Twenty Four1 [Member] Performance Based Restricted Stock Units Two Thousand Twenty Four [Member] Increase decrease in accrued and other liabilities noncurrent. Increase Decrease In Accrued And Other Liabilities Noncurrent Accrued liabilities and other long-term liabilities Entity Filer Category Accrued Liabilities, Current [Abstract] Contract With Customer Liability Additions Contract with customer liability additions. Additions Research and development service fees Research And Development Service Fees Research and development service fees. Asset Class [Axis] Total liabilities Liabilities Purchases of short term investments Payments to Acquire Short-Term Investments Beginning balance Ending balance Equity, Attributable to Parent Total stockholders' deficit Net Income (loss) Net loss Schedule of Research and Development Arrangement, Contract to Perform for Others [Table] Schedule Of Subleasing. Schedule Of Subleasing [Table Text Block] Schedule Of Subleasing Statement of Financial Position [Abstract] Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Shares used to compute net income (loss) per share, Diluted Weighted-average common shares, diluted Weighted-average common shares outstanding used to calculate diluted net income (loss) per share Weighted Average Number of Shares Outstanding, Diluted Credit Facility [Axis] Number of research targets selected Number Of Research Targets Selected Number of research targets selected. Price per share Shares Issued, Price Per Share Net income (loss) per share, Basic Basic Income (Loss) from Continuing Operations, Per Basic Share Short-term Investments, Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost Investments, Amortized Cost Trading Arrangemnt Expiration Date Trd Arr Expiration Date Trading arrangemnt expiration date. Seattle Genetics Agreement Seattle Genetics Agreement [Member] Seattle genetics agreement. Use of Estimates Use of Estimates, Policy [Policy Text Block] Income Tax Disclosure [Text Block] Income Taxes Change of estimates. Change of Estimates Change in estimates Balances, beginning of the period Balances, end of the period Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Summary of Calculation of Basic and Diluted Net Income (Loss) Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Number of targets selected Number Of Targets Selected Number of targets selected. Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Fair Value Disclosures [Abstract] Fair Value Hierarchy and NAV Fair Value Hierarchy and NAV [Axis] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Payments to Acquire Property, Plant, and Equipment, Total Type of Restructuring [Domain] Units vested PSU's vested Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Units vested Issuance of common stock in follow-on offering, net of issuance costs, shares Stock Issued During Period, Shares, New Issues Payroll and related expenses Employee-related Liabilities, Current Employee-related Liabilities, Current, Total Other comprehensive income (loss): Other Comprehensive Income (Loss), Tax [Abstract] Cash, cash equivalents and restricted cash, end of year Cash, cash equivalents and restricted cash, beginning of year Total Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations Class of Warrant or Right [Axis] Income Tax Disclosure [Abstract] Finite-Lived Intangible Assets by Major Class [Axis] Upfront Fee Received Upfront fee received. Upfront fee received Collaboration target research term Collaboration Target Research Term Collaboration target research term.