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AOCI Attributable to Parent [Member] Accumulated Other Comprehensive Income Convertible preferred stock Preferred Stock, Value, Issued, Ending Balance Preferred Stock, Value, Issued, Beginning Balance Preferred Stock, Value, Issued, Total Preferred Stock, Value, Issued Minimum Minimum [Member] Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value PSU's awarded Units Awarded Units awarded Current assets: Assets, Current [Abstract] Investment income (loss) per share Investment Income (Loss) Per Share Investment income (loss) per share. 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Common stock issuance costs included in accrued liabilities General and Administrative Expense General and Administrative Expense [Member] General and administrative 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) 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 per share Shares used to compute net income (loss) per share, Basic Regeneron Regeneron Pharmaceuticals, Inc Regeneron Pharmaceuticals, Inc [Member] Regeneron Pharmaceuticals, Inc member. Share-Based Payment Arrangement, Plan Modification, Incremental Cost Incremental cost Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Proceeds from Issuance of Private Placement Gross proceeds from issuance of private placement Subsequent Event Subsequent Events [Text Block] APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Total APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Stock-based compensation CX-801 (IFNAlpha2b) [Member] CX-801 (IFNAlpha2b). CX-801 (IFNAlpha2b) Equity, Attributable to Parent Ending balance Beginning balance Total stockholders' equity Basis of Accounting, Policy [Policy Text Block] Basis of Presentation Statement of Stockholders' Equity [Abstract] Share Based Compensation Award Tranche Two Share-Based Payment Arrangement, Tranche Two [Member] Depreciation and amortization Depreciation And Amortization Excluding Amortization Of Intangible Assets Depreciation and amortization excluding amortization of intangible assets. Type of Restructuring [Domain] Use of Estimates, Policy [Policy Text Block] Use of Estimates Achieving additional targets. Achieving Additional Targets [Member] Each Of Two Additional Targets First Phase 3 Study First Phase Three Study [Member] First phase three study. Collaborative Arrangement [Member] Collaborative Arrangement Entity Address, Address Line Two Fair Value Measurements and Investments Fair Value Disclosures [Text Block] Number of additional collaboration target. Number Of Additional Collaboration Target Number of additional collaboration target Warrants and Rights Note Disclosure [Abstract] Additional contingent payments. Additional Contingent Payments [Member] Additional Contingent Payments Number of Options Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] Schedule of Accrued Liabilities [Table Text Block] Schedule of Accrued Liabilities Exercise of stock options and release of RSUs, shares Share-based compensation arrangement by share-based payment award, exercise of stock options and release of restricted stock units in period. Share-based Compensation Arrangement By Share-based Payment Award, Exercise of Stock Options and Release of Restricted Stock Units in Period Noncash Investing and Financing Items [Abstract] Supplemental disclosures of noncash investing items: Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration] Regulatory Approval and Commercial Milestone [Member] Regulatory approval and commercial milestone. Regulatory approval and commercial milestone Collaboration and License Agreements Collaboration and License Agreements [Text Block] Collaboration and License Agreements [Text Block] Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Estimate of Transaction Price Cumulative adjustment from a change in estimate Astellas Pharma Inc. Astellas Pharma Inc [Member] Astellas Astellas Pharma Inc. 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] Time based restricted stock units. Time Based Restricted Stock Units [Member] Time based RSUs Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights Vesting rights, description Class of Warrant or Right, Outstanding Number of Warrants Outstanding Number of warrants, Beginning Number of Warrants, Ending Number of Warrants, Ending Extension of research term for each collaboration target. Extension Of Research Term For Each Collaboration Target Extension of research term for each collaboration target Number of collaboration target. Number Of Collaboration Target Number of collaboration target Class of Warrant or Right [Table] Entity Address, City or Town Restructuring Reserve, Translation and Other Adjustment Non-cash charges Pre-Funded Warrant. 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Number Of Oncology Target Number of oncology target Statement of Financial Position [Abstract] RSUs Restricted Stock Units (RSUs) [Member] Antidilutive Security, Excluded EPS Calculation [Table] Vesting [Axis] 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. Deferred revenue recognition maturity year. Deferred Revenue Recognition Maturity Year Deferred Revenue Recognition Maturity Year 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 Weighted-average common shares outstanding used to calculate diluted net income per share Shares used to compute net income (loss) per share, Diluted 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 US Treasury Securities [Member] U.S. Treasury Securities Number of Operating Segments Number of operating segments Sale of Stock [Domain] Segment Reporting Disclosure [Text Block] Segment Disclosures General and Administrative Expense, Total General and Administrative Expense General and administrative General and administrative expenses Milestone payment Milestone payment. Milestone Payment Milestone payable Research and Development Arrangement, Contract to Perform for Others [Line Items] License Agreement [Line Items] Rule 10b51 Arr Modified Flag Rule 10b51 arrangement modified flag. Rule 10b51 Arrangement Modified Flag Adjustments to Additional Paid in Capital, Warrant Issued Issuance of pre-funded warrants in follow on offering, net of issuance cost Recently Issued Accounting Standards Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Deferred revenue, current portion Contract with Customer, Liability, Current Severance and Benefits Costs Employee Severance [Member] Performance Based Restricted Stock Units Twenty Twenty Five [Member] Performance based restricted stock units two thousand twenty five. 2025 Performance based RSU Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Unrecognized tax benefits,income tax penalties and interest expense CX-904 (EGFRxCD3) [Member] CX-904 (EGFRxCD3) [Member] CX-904 (EGFRxCD3) Right to expand the number of additional collaboration target. 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 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 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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Deferred Revenue Recognition Maturity Year One Revenues, Total Revenues Revenue Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Net cash (used in) provided by investing activities Private Placement [Member] Private Placement Title of 12(b) Security Schedule of Segment Reporting Information, by Segment [Table] Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Option forfeited/expired Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value PSU's cancelled Units forfeited Money market funds Money Market Funds [Member] Income Taxes Income Tax Disclosure [Text Block] 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. 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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 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 Subsequent Event Type [Axis] 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 Equity Components [Axis] Equity Components Equity Component [Domain] Equity Component Asset Class [Axis] Statement of Comprehensive Income [Abstract] Future contingent milestone payment receivable. Contingent Milestone Payments Receivable Contingent milestone payments receivable Maximum [Member] Maximum Statistical Measurement [Axis] Statistical Measurement Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Options exercised Contract with Customer, Liability, Noncurrent Deferred revenue, net of current portion Common stock Common Stock, Value, Issued, Ending Balance Common Stock, Value, Issued, Beginning Balance Common Stock, Value, Issued, Total Common Stock, Value, Issued Income (Loss) from Continuing Operations, Per Diluted Share Diluted Net income (loss) per share, Diluted Non Rule 10b51 Arr Modified Flag Non Rule 10b51 arrangement modified flag. Non-Rule 10b51 Arrangement Modified Flag Proceeds from Collaborators Upfront payment received Clinical Development Milestone Payment Clinical development milestone payment Entity Registrant Name Other Nonoperating Income (Expense), Total Other Nonoperating Income (Expense) Other (expense) income, net Other income (expense), net 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 Subsequent Events [Abstract] 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. Cash payment Payments for Restructuring Cash payment 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 Restructuring Cost [Table] 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 Counterparty Name [Domain] Counterparty Name 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. 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 One Time Severance Payments and Other Employee Related Costs [Member] One Time Severance Payments and Other Employee Related Costs [Member] One Time Severance Payments and Other Employee Related Costs 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 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 Number of research targets selected. Number Of Research Targets Selected Number of research targets selected 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 Share Price Common stock, shares issuable under agreement, price per share Clinical Development Milestones [Member] Clinical development milestones. Clinical development milestones Change in estimates Change of Estimates Change of estimates. Local Phone Number Number of targets selected. Number Of Targets Selected Number of targets selected Restructuring Costs Restructuring Costs, Total Restructuring costs 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 Class of Stock [Domain] Class of Stock Accrued Professional Fees, Current Legal and professional expenses Stock, Class of Stock [Table] Collaboration target research term. Collaboration Target Research Term Collaboration target research term Entity Emerging Growth Company