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Zenas BioPharma, Inc. [Member] Represents information pertaining to Zenas bio pharma. 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[Member] Counterparty Name [Axis] Counterparty Name [Axis] Liabilities and Stockholders’ Equity Liabilities and Equity [Abstract] Intangible Asset, Finite-Lived, Class [Domain] Intangible Asset, Finite-Lived, Class [Domain] Weighted-average remaining contractual term, exercisable Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted-Average Remaining Contractual Term XmAb412 (TL1A x IL-23p19) XmAb412 (TL1A x IL-23p19) [Member] XmAb412 (TL1A x IL-23p19) 2030 Lessor, Operating Lease, Payment to be Received, Year Four Marketable Securities [Abstract] Marketable Securities [Abstract] Award Type [Domain] Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount For the remainder of 2026 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Fair Value Measurements Fair Value Disclosures [Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] Supplemental 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[Member] Represents information pertaining to the counterparty, INmune Bio, Inc. (INmune). Award Type [Axis] Award Type [Axis] For the remainder of 2026 Lessor, Operating Lease, Payment to be Received, Remainder of Fiscal Year Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Accounts receivable Accounts Receivable, after Allowance for Credit Loss, Current Cash paid to acquire noncontrolling interest Advance Future Royalty And Milestone Payments Advance Future Royalty And Milestone Payments Accumulated deficit Retained Earnings (Accumulated Deficit) Product and Service [Axis] Product and Service [Axis] Marketable equity securities Equity Securities, FV-NI Restricted cash Restricted Cash, Noncurrent Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Alexion Alexion [Member] Alexion Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock Common Stock [Member] Fair Value Estimated Fair Value Marketable debt securities Debt Securities, Available-for-Sale Expected volatility (as a percent) Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Operating lease cost Operating Lease, Cost Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract] Reportable Segment Reportable Segment [Member] Reportable Segment Expected dividend yield Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate OCM Life Sciences Portfolio LP (OMERS) OCM Life Sciences Portfolio LP (OMERS) [Member] OCM Life Sciences Portfolio LP (OMERS) 2031 and thereafter Lessor, Operating Lease, Payment To Be Received, Year Five And Thereafter Lessor, Operating Lease, Payment To Be Received, Year Five And Thereafter Equity Awards Adjustments Equity Awards Adjustments [Member] Collaboration and Licensing Agreements Collaborative Arrangement Disclosure [Text Block] Total liabilities and stockholders’ equity Liabilities and Equity Variable lease cost Variable Lease, Cost Stock options Share-Based Payment Arrangement, Option [Member] Liabilities related to the sales of future royalties Debt, Current Noncontrolling interest Equity, Attributable to Noncontrolling Interest Schedule of Future Minimum Sublease Receipts Lessor, Operating Lease, Payment to be Received, Maturity [Table Text Block] Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Plan Name [Axis] Plan Name [Axis] Pasadena, CA - Office and Laboratory Space Pasadena, CA - Office And Laboratory Space [Member] Represents information pertaining to the laboratory and office space in Pasadena, California. Marketable debt securities Debt Securities, Current Tabular List, Table Tabular List [Table Text Block] Additional paid-in capital Additional Paid in Capital Other, net Other Nonoperating Income (Expense) 2029 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three For the remainder of 2026 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Remainder of Fiscal Year Name Awards Close in Time to MNPI Disclosures, Individual Name Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Aggregate intrinsic value, balance outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Schedule of Marketable Equity Securities Debt Securities, Trading, and Equity Securities, FV-NI [Table Text Block] Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period General and administrative General and administrative General and Administrative Expense Long-Lived Asset, Class [Domain] Long-Lived Asset, Class [Domain] MorphoSys MorphoSys [Member] Represents information pertaining to MorphoSys. 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Entity Address, Address Line Two Entity Address, Address Line Two Exercise of stock options (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Net loss including noncontrolling interest Net loss Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Current assets: Assets, Current [Abstract] Weighted-average remaining lease term (in years) Operating Lease, Weighted Average Remaining Lease Term Non-PEO NEO Non-PEO NEO [Member] Entity Address, Address Line One Entity Address, Address Line One Weighted average grant date fair value, vested (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Subsidiary, Sale of Stock [Line Items] Subsidiary, Sale of Stock [Line Items] Income tax (benefit) expense Income tax (benefit) expense Income Tax Expense (Benefit) XmAb942 (Xtend TL1A) XmAb942 (Xtend TL1A) [Member] XmAb942 (Xtend TL1A) Award Timing Method Award Timing Method [Text Block] Net (decrease) increase in cash, cash equivalents, and restricted cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forecast Forecast [Member] Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Expected volatility, low end of range (as a percent) Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum 2028 Lessor, Operating Lease, Payment to be Received, Year Two Proceeds from legal settlements Proceeds from Legal Settlements Net loss attributable to Xencor, Inc. 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