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Liability Related To Sale Of Future Royalties And Milestones Including Unamortized Transaction Costs Liability related to sale of future royalties and milestones - ending balance Liability related to sale of future royalties and milestones - beginning balance Director [Member] Dr. Jennifer Buell [Member] Dr. Jennifer Buell Subsequent Event Type [Axis] Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Cash flows from financing activities: Accrued Liabilities Accounts Payable and Accrued Liabilities Disclosure [Text Block] Schedule of Equity Method Investments [Line Items] Noncontrolling Interest Disclosure [Text Block] Non-controlling Interest Equity Components [Axis] Equity Components Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term Options Vested or expected to vest, Weighted Average Remaining Contractual Term Percentage of synthetic royalty on worldwide net sales of purchased assets. 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Transaction expenses Nonoperating Income (Expense) [Abstract] Other expense: Other income (expense): Non Cash Consideration Excluded From Transaction Price Non-cash consideration excluded from transaction price. Non-cash consideration excluded from transaction price Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Investment Company, Nonconsolidated Subsidiary, Summarized Financial Information [Table Text Block] Summarized Balance Sheet Information and Results of Operations Non-US [Member] Rest of World [Member] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Schedule of Anti-dilutive Securities Excluded from Computation of Diluted Weighted Average Shares Outstanding Entity Interactive Data Current Entity Interactive Data Current Increase (Decrease) in Contract with Customer, Liability Deferred revenue Reduction in revenue Statement of Income Location, Balance [Domain] Income Statement Location Fair Value Measurement [Domain] Fair Value Measurement Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Cash flows from operating activities: Proceeds from liability related to sale of future royalties and milestones Proceeds from sale of future royalties and milestones Proceeds From Sale Of Future Royalties And Milestones Proceeds from sale of future royalties and milestones. Litigand [Member] Ligand Pharmaceuticals Incorporated. Ligand Pharmaceuticals Incorporated [Member] Ligand Pharmaceuticals Incorporated [Member] Accounting Standards Update and Change in Accounting Principle [Text Block] Recent Accounting Pronouncements Auction Market Preferred Securities, Stock Series, Liquidation Value Series A-1 convertible preferred stock, liquidation value Cash equivalents Cash Equivalents, at Carrying Value Cash Equivalents, at Carrying Value, Total Cash equivalents Purchaser Upsize Option Purchaser Upsize Option Purchaser upsize pption Purchaser Upsize Option (Note F) Stock Issued During Period, Shares, Issued for Services Issuance of shares for services, shares Entity Tax Identification Number Entity Tax Identification Number Revenues [Abstract] Revenue: Long-Term Debt, Type [Axis] Long-Term Debt, Type Payment for Services [Member] Payment for services [Member] Payment For Services [Member] Liability related to sale of future royalties and milestones. Liability Related To Sale Of Future Royalties And Milestones [Table] Liability Related To Sale Of Future Royalties And Milestones [Table] Zydus License Agreement [Member] Zydus license agreement. Zydus License Agreement Proceeds from Issuance or Sale of Equity Net proceeds from sale of equity Proceeds from Issuance or Sale of Equity, Total Local Phone Number Local Phone Number EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedOtherThanOptionsPeriodForRecognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedOtherThanOptionsPeriodForRecognition1 Unrecognized share-based compensation expense, weighted average period, Other than option Related Party Transaction [Domain] AAC Program [Member] AAC program. Total Other Liabilities, Current Other current liabilities Unrecognized share-based compensation expense Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Deferred Compensation Arrangement with Individual, Share-Based Payment [Table] Schedule Of Deferred Compensation Arrangement With Individual Share Based Payments [Table] Trademarks [Member] Trademarks [Member] Stock issued during period value stock options exercised and employee stock purchase plan. Stock Issued During Period Value Stock Options Exercised And Employee Stock Purchase Plan Exercise of stock options and employee share purchases Accounting Policies [Abstract] Other Current Liabilities [Member] Other Current Liabilities [Member] Disaggregation of Revenue [Line Items] Disaggregation Of Revenue [Line Items] Total revenues Revenue Revenues Earnings Per Share, Basic, by Common Class, Including Two-Class Method [Table] Liability related to sale of future royalties and milestones payment current. Liability Related To Sale Of Future Royalties And Milestones Payment Current Current portion, liability related to sale of future royalties and milestones Stock Issued During Period, Value, Connection With Debt Agreement Stock issued during period value connection with debt agreement. Issuance of shares in connection with debt agreement Class of Stock [Domain] Class of Stock Labor and Related Expense Payroll related expenses Unrecognized share-based compensation expense, weighted average period Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Accrued Professional Fees, Current Professional fees Cash, Cash Equivalents, and Short-Term Investments Cash equivalents and short term investments Cash, Cash Equivalents, and Short-Term Investments, Total Cash, cash equivalents and short term investment Stock, Class of Stock [Table] Schedule Of Stock By Class [Table] Entity Emerging Growth Company Entity Emerging Growth Company