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Statistical Measurement [Domain] Statistical Measurement [Domain] Title of 12(b) Security Title of 12(b) Security Debt Securities, Available-for-Sale [Table] Debt Securities, Available-for-Sale [Table] Document Fiscal Year Focus Document Fiscal Year Focus Increase (decrease) in fair value of contingent value right liability Increase (Decrease) In Fair Value Of Contingent Value Right Liability Increase (Decrease) In Fair Value Of Contingent Value Right Liability Adjustment to Compensation, Amount Adjustment to Compensation Amount Financial Instrument [Axis] Financial Instrument [Axis] Segment Reporting [Abstract] Common stock, $0.0001 par value; 400,000,000 shares authorized as of June 30, 2026 and December 31, 2025; 88,064,133 shares and 78,189,811 shares issued and outstanding as of June 30, 2026 and December 31, 2025, respectively. 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Amendment Flag Amendment Flag CURRENT LIABILITIES Liabilities, Current [Abstract] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Disposal Group Classification [Axis] Disposal Group Classification [Axis] Marketable securities, gross unrealized losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Cash milestone payments License Agreement, Milestone Payments License Agreement, Milestone Payments Related Party Transactions Related Party Transactions Disclosure [Text Block] Total related party accounts payable Accounts Payable, Other, Current Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Entity Address, State or Province Entity Address, State or Province Total, unrealized losses Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss Options granted to purchase (in shares) Stock options, Grants (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross Fair Value Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract] PEO Total Compensation Amount PEO Total Compensation Amount Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Financial Assets: Assets, Fair Value Disclosure [Abstract] Asset Acquisition [Axis] Asset Acquisition [Axis] Cash and Cash Equivalents [Abstract] Accrued and other liabilities Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities Weighted-average common stock outstanding, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Share-Based Payment Arrangement, Tranche One Share-Based Payment Arrangement, Tranche One [Member] Schedule of Expenses Related to Related Party Which are Settled in Cash Schedule of Related Party Transactions [Table Text Block] Net accretion of discount on marketable securities Accretion (Amortization) of Discounts and Premiums, Investments Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Global Rights to Pegzilarginase Global Rights To Pegzilarginase [Member] Global Rights To Pegzilarginase Number of reportable segments Number of Reportable Segments Total current liabilities Liabilities, Current Licensing Agreements [Abstract] Licensing Agreements CVR liability Derivative Liability, Current Entity Address, City or Town Entity Address, City or Town Reportable Segment Reportable Segment [Member] Reportable Segment Restricted stock units, Grants (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Preferred stock issued and outstanding (as percent) Preferred Stock Remains Issued and Outstanding Percentage. Preferred stock remains issued and outstanding percentage. 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Document Period End Date Document Period End Date Changes in operating assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Net cash (used in) provided by investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Preferred Stock, Excluding Series A Non Voting Convertible Preferred Stock Preferred Stock, Excluding Series A and B Non Voting Convertible Preferred Stock [Member] Preferred Stock, Excluding Series A and B Non Voting Convertible Preferred Stock Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Compensation Compensation Expense, Excluding Cost of Good and Service Sold Accrued and Other Current Liabilities Accrued And Other Current Liabilities [Text Block] The entire disclosure for accrued expenses, and other liabilities that are classified as current at the end of the reporting period. 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October 2025 Underwritten Offering October 2025 Underwritten Offering [Member] October 2025 Underwritten Offering Convertible Preferred Stock and Stockholders' Equity Preferred Stock [Text Block] Sale of stock, authorized amount Sale of Stock, Authorized Amount Sale of Stock, Authorized Amount Accrued contracted research and development costs Accrued Contracted Research And Development Costs Accrued contracted research and development costs. 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Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Operating expenses: Operating Expenses [Abstract] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Annual percentage of additional shares Annual Percentage Of Additional Shares Which Equals To Issued And Outstanding Shares Annual percentage of additional shares which equals to the issued and outstanding shares. Schedule of Weighted-Average Assumptions Used in Calculating Fair Value of Awards Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] City Area Code City Area Code Accumulated Other Comprehensive Income AOCI Attributable to Parent [Member] Termination notice period (in days) Termination Notice Period Termination Notice Period All Individuals All Individuals [Member] Series A Non Voting Convertible Preferred Stock Series A Non-Voting Convertible Preferred Stock Series A Preferred Stock Series A Non Voting Convertible Preferred Stock [Member] Series A non voting convertible preferred stock. Name Forgone Recovery, Individual Name Contingent Value Rights Commitments and Contingencies, Policy [Policy Text Block] Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Statement [Line Items] Statement [Line Items] TOTAL ASSETS Assets Interest income Investment Income, Net Preferred stock, issued (in shares) Preferred Stock, Shares Issued Common stock available for future issuance (in shares) Common Stock, Capital Shares Reserved for Future Issuance Milestone payments, outstanding and payable License Agreement, Milestone Payments Outstanding and Payable License Agreement, Milestone Payments Outstanding and Payable Operating Segments Operating Segments [Member] Conversion of Series B non-voting convertible preferred stock into common stock Conversion of Stock, Amount Converted Marketable securities, gross unrealized gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Stock-Based Compensation Share-Based Payment Arrangement [Text Block] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Issuance of common stock in connection with at-the-market and follow-on offering program, net of financing costs (in shares) Stock Issued During Period, Shares, New Issues Related party accounts payable Accounts Payable and Other Accrued Liabilities, Current PEO PEO [Member] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Stock-based compensation expense Total stock-based compensation expense Share-Based Payment Arrangement, Expense Other non-current liabilities Other Liabilities, Noncurrent Common stock available for future issuance, additional amount authorized (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Restricted stock units, Weighted Average Grant Date Fair Value (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 Money market funds Cash equivalents, amortized cost Cash Equivalents, at Carrying Value Due in one year or less Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Payables and Accruals [Abstract] Accumulated Deficit Retained Earnings [Member] Total operating expenses Operating Expenses Money market funds Money market funds Money Market Funds [Member] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Schedule of Significant Inputs Used to Estimate the Fair Value of CVR Liability Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Unrealized (loss) gain on marketable securities OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Common stock, outstanding (in shares) Beginning balance, common stock (in shares) Ending balance, common stock (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Net loss per share, diluted (in dollars per share) Earnings Per Share, Diluted Entity Current Reporting Status Entity Current Reporting Status Net cash provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Total Shareholder Return Amount Total Shareholder Return Amount Cash Equivalents And Marketable Securities [Table] Cash Equivalents And Marketable Securities [Table] Cash equivalents and marketable securities. Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Liabilities: Liabilities, Fair Value Disclosure [Abstract] Ownership [Domain] Ownership [Domain] Research and development, excluding compensation and share-based compensation Research and Development Expense Adjustments to reconcile net loss to net cash used in operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Allocation of deferred offering costs against proceeds of issuance of common stock Deferred Offering Costs, Allocated Amount of Proceeds of Issuance of Common Stock Deferred Offering Costs, Allocated Amount of Proceeds of Issuance of Common Stock Share-Based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] CASH FLOWS FROM FINANCING ACTIVITIES Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] 2016 ESPP 2016 ESPP [Member] 2016 ESPP Financial Instruments [Domain] Financial Instruments [Domain] Numerator Net Income (Loss) Available to Common Stockholders, Basic [Abstract] Paragon Therapeutics Inc Paragon Therapeutics Inc [Member] Paragon therapeutics, Inc. Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Issuance of common stock in connection with at-the-market and follow-on offering program, net of financing costs Stock Issued During Period, Value, New Issues Over-Allotment Option Over-Allotment Option [Member] Number of domestic banking institutions (in banks) Number Of Domestic Banking Institutions Number Of Domestic Banking Institutions Proceeds from employee stock option exercises and employee stock plan purchases Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Including Option Exercised Preferred Stock Preferred Stock [Member] Sublicensing fee, outstanding and payable Sublicensing Fee, Outstanding And Payable Sublicensing Fee, Outstanding And Payable Sublicensing fee Sublicensing Fee Sublicensing Fee Segment Reporting [Table] Segment Reporting [Table] Related Party Transaction [Table] Related Party Transaction [Table] Sale of Stock [Axis] Sale of Stock [Axis] Number of monthly installments Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Monthly Installments Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Monthly Installments All Trading Arrangements All Trading Arrangements [Member] Less Than 12 Months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Beginning balance Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Loss from operations Operating Income (Loss) Current Fiscal Year End Date Current Fiscal Year End Date Proceeds from stock option exercises received in subsequent period Issuance of Convertible Preferred Stock Related to Private Placement, Unpaid Amount Issuance of Convertible Preferred Stock Related to Private Placement, Unpaid Amount Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Related Party Transaction [Domain] Related Party Transaction [Domain] Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Entity File Number Entity File Number At-The-Market Offering, 2026 Sales Agreement At-The-Market Offering, 2026 Sales Agreement [Member] At-The-Market Offering, 2026 Sales Agreement Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Sale of stock, remaining authorized amount Sale of Stock, Remaining Authorized Amount Sale of Stock, Remaining Authorized Amount Stock-based compensation expense Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture Schedule of Contractual Maturities of Marketable Securities at Estimated Fair Value Investments Classified by Contractual Maturity Date [Table Text Block] Corporate bonds Corporate bonds Corporate bonds Corporate Bond Securities [Member] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Common stock, issued (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] Percentage of ownership held in third party Minority Interest Ownership Percentage By Noncontrolling Owners Held In Third Party Minority interest ownership percentage by noncontrolling owners held in third party. 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