Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Statistical Measurement Statistical Measurement [Domain] Summary of Available-For-Sale Securities Recorded in Cash and Cash Equivalents or Marketable Securities Debt Securities, Available-for-Sale [Table Text Block] Interest rate increase of sublease income per year Interest Rate Increase of Sublease Income Per Year Interest rate of sublease income per year Award Timing Predetermined Award Timing Predetermined [Flag] Collaborative agreement upfront payments collected Collaborative agreement upfront payments collected Collaborative agreement upfront payments collected. Performance-Based Stock Options Performance-Based Stock Options [Member] Performance based stock options. Entity File Number Entity File Number Deposits for operating lease Other Assets Deposits For Operating Lease, Noncurrent Other assets deposits for operating lease. ADDITIONAL PAID-IN CAPITAL Additional Paid-in Capital [Member] Debt Issuance Costs and Debt Discounts Debt, Policy [Policy Text Block] Intercompany debt forgiveness Effective Income Tax Rate Reconciliation, Intercompany Debt Forgiveness, Amount Effective Income Tax Rate Reconciliation, Intercompany Debt Forgiveness, Amount Impairment of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Tabular List, Table Tabular List [Table Text Block] Leases [Abstract] Leases [Abstract] Recently Issued Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Reverse stock split rounding adjustment (in shares) Stock Issued During Period, Shares, Reverse Stock Splits SOFR Secured Overnight Financing Rate (SOFR) [Member] Type of Restructuring [Domain] Type of Restructuring [Domain] Retirement Plan Name Retirement Plan Name [Axis] Accrued preclinical and research costs Accrued Preclinical And Research Costs Current Accrued preclinical and research costs, current. Research and development credit Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount Unrealized Losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Pre-funded warrants outstanding (in shares) Class of Warrant or Right, Outstanding Net loss per common share, basic (in dollars per share) Net loss per common share, Basic (in dollars per share) Earnings Per Share, Basic Other expenses Other Expenses Adjustment to Compensation: Adjustment to Compensation [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Commercial paper Commercial Paper [Member] Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities shares available for future issuance (in shares) Common Stock, Capital Shares Reserved for Future Issuance Non-cash charges Restructuring Reserve, Settled without Cash Net operating loss (NOL) carryforwards indefinite Operating Loss Carryforwards Indefinite Operating loss carryforwards, indefinite. Gross deferred tax assets Deferred Tax Assets, Gross Unbilled receivable from Everest (Note 10) Unbilled Receivables, Current Total current Current Income Tax Expense (Benefit) Adjustment to Compensation, Amount Adjustment to Compensation Amount Unamortized debt discount and issuance costs Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Other assets Increase (Decrease) in Other Operating Assets Basis of Presentation and Consolidation Consolidation, Policy [Policy Text Block] Stock-based compensation Share-Based Payment Arrangement, Noncash Expense Options Options to purchase common stock Share-Based Payment Arrangement, Option [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Initial upfront payments total Proceeds from Sale of Productive Assets Schedule Of Property Plant And Equipment [Table] Property, Plant and Equipment [Table] Research and Development Costs Research and Development Expense, Policy [Policy Text Block] Audit Information [Abstract] Audit Information Preferred stock, convertible, conversion ratio Preferred Stock, Convertible, Conversion Ratio Cash equivalents Cash and Cash Equivalents [Member] Organization And Description Of Business [Table] Organization And Description Of Business [Table] Organization and description of business. Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Percent Effective Income Tax Rate Reconciliation, Percent [Abstract] Antidilutive Securities Antidilutive Securities [Axis] Asset impairments Asset Impairment Charges Total stockholders' equity Beginning balance Ending balance Equity, Attributable to Parent Measurement Frequency Measurement Frequency [Axis] Insider Trading Policies and Procedures [Line Items] Total stock-based compensation expense Share-Based Payment Arrangement, Expense Accrued severance related costs Accrued Severance Related Costs, Current Accrued Severance Related Costs, Current Summary of Property and Equipment, Net Property, Plant and Equipment [Table Text Block] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Current assets: Assets, Current [Abstract] Options cancelled/forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures in Period Total liabilities and stockholders' equity Liabilities and Equity Foreign Currency Translation Foreign Currency Transactions and Translations Policy [Policy Text Block] Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Fair Value, Measurements, Recurring Fair Value, Recurring [Member] Number of Options Outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] Concentration of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Liabilities and Stockholders' Equity Liabilities and Equity [Abstract] State State and Local Jurisdiction [Member] Cover Cover [Abstract] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Maximum Maximum [Member] General and administrative General and Administrative Expense [Member] Accounting Policies [Abstract] Accounting Policies [Abstract] Summary of Maturities of Lease Liabilities Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block] Principal loan balance Debt, Gross Debt, Gross 2022 Stock Inducement Plan Two Thousand Twenty Two Stock Incentive Plan [Member] Two thousand twenty two stock incentive plan member. Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Debt Instrument [Line Items] Debt Instrument [Line Items] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Pay vs Performance Disclosure [Line Items] Debt, net Debt, Long-Term and Short-Term, Combined Amount Class of Warrant or Right [Axis] Class of Warrant or Right [Axis] Operating lease liability Total lease liabilities Total lease liabilities Operating Lease, Liability U.S. agency bonds U.S. Government agency bonds US Government Agencies Debt Securities [Member] Additional milestone payments on achievement Additional Payments Receivable On Milestone Achievements Additional Payments Receivable On Milestone Achievements Retirement Benefits [Abstract] Retirement Benefits [Abstract] Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Underwritten Public Offering Underwritten Public Offering [Member] Underwritten public offering. Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Total Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company Schedule of Long-Term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Proceeds from sale of equipment Proceeds from Sale of Property, Plant, and Equipment Summary Of Significant Accounting Policies [Table] Summary Of Significant Accounting Policies [Table] Summary of significant accounting policies. Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Options to purchase of common stock outstanding (in shares) Options To Purchase Of Common Stock Outstanding Options to purchase of common stock outstanding. Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Cash Cash Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Participants of plan per contribution Defined Contribution Plan Per Contribution By Participants Defined contribution plan per contribution by participants. Name Measure Name Beginning balance Ending balance Restructuring Reserve Summary of Domestic and Foreign Components of Net Loss Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Domestic Income (Loss) from Continuing Operations before Income Taxes, Domestic Summary of Stock-Based Compensation Expense Recognized Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Operating lease liabilities, current Operating Lease, Liability, Current Internal costs Internal Costs [Abstract] Internal Costs Document Fiscal Period Focus Document Fiscal Period Focus Award Timing Method Award Timing Method [Text Block] Award Type Award Type [Axis] Total assets Assets Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Stock-Based Compensation Share-Based Payment Arrangement [Policy Text Block] Trading Symbol Trading Symbol 2018 Equity Incentive Plan Two Thousand Eighteen Equity Incentive Plan [Member] Two thousand eighteen equity incentive plan. RSUs vested (in usd 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 Deposits for operating lease Other Assets Deposits For Operating Lease, Current Other Assets Deposits For Operating Lease, Current Equal To Sum Of A Equal To Sum Of A [Member] Equal to the sum of (a). Geographical Geographical [Domain] Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Income Taxes Income Tax, Policy [Policy Text Block] Entity Address, City or Town Entity Address, City or Town Cash flows from operating activities: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Research and development credit Effective Income Tax Rate Reconciliation, Tax Credit, Research, Percent Other segment items Segment Reporting, Other Segment Item, Amount Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Net deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Statement of Income Location, Balance Statement of Income Location, Balance [Domain] Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Severance and related benefit costs Severance Costs Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Entity Emerging Growth Company Entity Emerging Growth Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Intercompany debt forgiveness Effective Income Tax Rate Reconciliation, Intercompany Debt Forgiveness, Percent Effective Income Tax Rate Reconciliation, Intercompany Debt Forgiveness, Percent Stock options shares outstanding (in shares) Outstanding, beginning balance (in shares) Outstanding, ending balance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number 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] Level 2 Fair Value, Inputs, Level 2 [Member] Document Financial Statement Error Correction [Flag] Document Financial Statement Error Correction [Flag] State and local income taxes, net of federal income tax effect Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Common stock, shares outstanding (in shares) Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding Summary of Components of Income Tax Expense (Benefit) Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Plan Name Plan Name [Axis] Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Document Information [Table] Document Information [Table] PEO PEO [Member] Severance and related benefit costs Employee Severance [Member] Reclassification of currency translation loss Cumulative Currency Translation Gains Losses Realized Upon Sale Or Liquidation Reclassified From Other Comprehensive Income Cumulative Currency Translation Gains Losses Realized Upon Sale Or Liquidation Reclassified From Other Comprehensive Income Discount rate of cash flow Lessor, Operating Lease, Discount Rate of Cash Flow Discount rate of cash flow Supplemental disclosures of noncash investing and financing information: Noncash Investing and Financing Items [Abstract] Interest income Investment Income, Interest Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Valuation allowance increased Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount 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] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Property and equipment Deferred Tax Liabilities, Property, Plant and Equipment ACCUMULATED DEFICIT Retained Earnings [Member] Prepaid expenses and other current assets Total prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Income Tax Jurisdiction Income Tax Jurisdiction [Axis] Number of RSUs Outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Effective interest rate percentage Debt Instrument, Interest Rate, Effective Percentage Summary of Accrued Liabilities Schedule of Accrued Liabilities [Table Text Block] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Share-Based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] Cash and cash equivalents at the beginning of period Cash and cash equivalents at the end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement [Abstract] Income Statement [Abstract] Provision for income taxes Provision for income taxes Income Tax Expense (Benefit) Line of credit facility, additional interest rate Debt Instrument, Basis Spread on Variable Rate Purchases of marketable securities Payments to Acquire Marketable Securities Sale of Stock Sale of Stock [Domain] Document Information [Line Items] Document Information [Line Items] Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Income Taxes Disclosure [Line Items] Income Taxes Disclosure [Line Items] Income taxes disclosure. Product and Service [Domain] Product and Service [Domain] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Total property and equipment Property, Plant and Equipment, Gross Total cash, cash equivalent and marketable securities Cash, Cash Equivalents, and Short-Term Investments Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Employer incurred matching contribution expenses Defined Contribution Plan, Employer Discretionary Contribution Amount Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] City Area Code City Area Code Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Advance for clinical-related costs, current Prepaid Advance For Clinical Related Costs, Current Prepaid advance for clinical related costs current. Accrued liabilities Total accrued liabilities Accrued Liabilities, Current Number of shares will increase automatically through every year on specified date Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Increase Automatically Through Every Year On Specified Date Share based compensation arrangement by share based payment award number of shares increase automatically through every year on specified date. Lessee Disclosure [Abstract] Lessee Disclosure [Abstract] Outstanding, beginning balance (in shares) Outstanding, ending balance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Class Of Warrant Or Right [Line Items] Class of Warrant or Right [Line Items] Cash flows from investing activities: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] General and administrative General and Administrative Expense Unrecognized stock-based compensation cost Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Net cash used in operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Collaboration Revenue Collaboration Revenue [Member] Collaboration revenue. Effective IncomeTax Rate Reconciliation [Table] Effective Income Tax Rate Reconciliation [Table] Sale of available-for-sale securities Proceeds from Sale of Debt Securities, Available-for-Sale Preferred Share Purchase Right Preferred Share Purchase Right [Member] Preferred Share Purchase Right Estimated useful lives of the assets Property, Plant and Equipment, Useful Life Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Subsequent Event Subsequent Event [Member] Summary of Fair Value of Employee Stock Options Granted and ESPP Rights to Purchase Common Stock Calculated Using Black Scholes Option Pricing Model with Weighted Average Assumptions Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Effective Income Tax Rate Reconciliation [Line Items] Effective Income Tax Rate Reconciliation [Line Items] Rent expense Lease, Cost Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Summary of Lease Liabilities Lease, Cost [Table Text Block] PEO Total Compensation Amount PEO Total Compensation Amount Depreciation expense Depreciation U.S. Treasury money market funds Money Market Funds [Member] Federal Deferred Federal Income Tax Expense (Benefit) Assets held for sale Asset, Held-for-Sale, Not Part of Disposal Group, Current Equity Components Equity Components [Axis] Property Plant And Equipment [Line Items] Property, Plant and Equipment [Line Items] Unrecognized Tax Benefits [Roll Forward] Unrecognized Tax Benefits [Roll Forward] Auditor Name Auditor Name Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Issuance of common stock under employee stock incentive plans (in shares) Issuance of Shares under Incentive and Share Based Compensation Plans, Shares Issuance of shares under incentive and share based compensation plans. Number of reportable segments Number of Reportable Segments Amgen, Inc Amgen Inc [Member] Amgen Inc Member Defined Contribution Plan Compensation and Employee Benefit Plans [Text Block] Schedule of Operating Leased Assets [Table] Schedule of Operating Leased Assets [Table] Supplemental disclosures Supplemental Cash Flow Information [Abstract] Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Other Performance Measure, Amount Other Performance Measure, Amount Weighted Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Debt, current Debt, Current Entity Address, State or Province Entity Address, State or Province Marketable Securities Marketable Securities, Policy [Policy Text Block] Impairment loss of right-of-use asset Impairment charge Operating Lease, Impairment Loss Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Antidilutive Security, Excluded EPS Calculation [Table] Fair Value Measurements Fair Value Measurement, Policy [Policy Text Block] Total current liabilities Liabilities, Current Amount Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract] Operating Leased Assets [Line Items] Operating Leased Assets [Line Items] Restructuring and related cost, number of positions eliminated, period percent Restructuring and Related Cost, Number of Positions Eliminated, Period Percent Individual: Individual [Axis] Vesting [Axis] Vesting [Axis] Restricted cash Restricted Cash Income Tax Jurisdiction Income Tax Jurisdiction [Domain] Payments of dividends of common stock Payments of Ordinary Dividends, Common Stock Document Annual Report Document Annual Report Research and development Research and Development Expense [Member] Additional paid-in capital Additional Paid in Capital, Common Stock Employees contributions amount up to lesser of pre-tax compensation Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount Net cash provided by investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation 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] Cash paid for interest Interest Paid, Excluding Capitalized Interest, Operating Activity Document Fiscal Year Focus Document Fiscal Year Focus Basis of Presentation and Consolidation Basis of Accounting, Policy [Policy Text Block] Operating lease right-of-use asset Operating Lease, Right-of-Use Asset Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Repayment of loan principal and final fee Repayments of Long-Term Debt Provision for income taxes Effective Income Tax Rate Reconciliation, Percent Entity Interactive Data Current Entity Interactive Data Current South San Francisco, California South San Francisco California [Member] South san Francisco, California. Decrease related to prior year tax positions Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Operating lease costs Operating Lease, Cost Asset impairments Asset Impairment [Member] Asset Impairment Member Plan Name Plan Name [Domain] Estimated weighted average amortization period (in years) Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Options exercised (in shares) Options exercised (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Valuation allowance Deferred Tax Assets, Valuation Allowance Equity [Abstract] Equity [Abstract] Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Cumulative accretion of final fee Cumulative Accretion of Final Fee Cumulative accretion of final fee. Stock-based compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Amount Segment Reporting Segment Reporting Disclosure [Text Block] Loan and Security Agreement Loan And Security Agreement [Member] Loan and security agreement. 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] U.S. Treasury securities US Treasury Securities [Member] Net operating loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards Federal Current Federal Tax Expense (Benefit) Long-Lived Tangible Asset Long-Lived Tangible Asset [Axis] R&D Capitalization Deferred Tax Assets RD Capitalization Deferred tax assets RD capitalization. Class Of Warrant Or Right [Table] Class of Warrant or Right [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Percentage of annual increase in number of common stock shares Share Based Compensation Arrangement By Share Based Payment Award Annual Increase In Number Of Common Stock Shares Percent Share based compensation arrangement by share based payment award annual increase in number of common stock shares percent. Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value, Recurring and Nonrecurring [Table] Leases Lessee, Leases [Policy Text Block] Intercompany debt forgiveness - foreign subsidiary Effective Income Tax Rate Reconciliation, Nondeductible Expense, Intercompany Debt Forgiveness, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Intercompany Debt Forgiveness, Percent Income Tax [Table] Income Tax [Table] Income ax. Depreciation and amortization Depreciation, Depletion and Amortization Other assets Total other assets Other Assets, Noncurrent Series A Junior Participating Preferred Stock Series A Junior Participating Preferred Stock [Member] Series A Junior Participating Preferred Stock Entity Central Index Key Entity Central Index Key PEO Name PEO Name Collaboration revenue Revenues Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Rate differential Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Arrangement Duration Trading Arrangement Duration Share-Based Payment Arrangement, Tranche One Share-Based Payment Arrangement, Tranche One [Member] Expected volatility, Maximum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Computer equipment Computer Equipment [Member] Savings and Investment Plan Savings And Investment Plan [Member] Savings and investment plan. Segments [Axis] Segments [Axis] Pre funded warrants exercise price (in dollars per share) Class of Warrant or Right, Exercise Price of Warrants or Rights Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Furniture, laboratory and office equipment Furniture Laboratory And Office Equipment [Member] Furniture, laboratory and office equipment. Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category Local Phone Number Local Phone Number Class of Stock [Domain] Class of Stock [Domain] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] U.S federal statutory tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Subsequent Event Type [Axis] Subsequent Event Type [Axis] Stock-Based Compensation Share-Based Payment Arrangement [Text Block] Assets Assets [Abstract] Debt, noncurrent Long-Term Debt, Excluding Current Maturities Credit Facility [Axis] Credit Facility [Axis] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Class of Warrant or Right [Domain] Class of Warrant or Right [Domain] Statement of Financial Position Location, Balance [Axis] Statement of Financial Position Location, Balance [Axis] Vesting [Domain] Vesting [Domain] Debt Instrument [Axis] Debt Instrument [Axis] RSUs forfeited (in usd per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Fair Value Measurements Fair Value Disclosures [Text Block] Loss on debt extinguishment Loss on extinguishment Gain (Loss) on Extinguishment of Debt Deferred tax assets Deferred Tax Assets, Net [Abstract] Credit Facility [Domain] Credit Facility [Domain] Stockholders' equity: Equity, Attributable to Parent [Abstract] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] RSUs vesting tranches (as a percent) Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Research and development Research and Development Expense ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) AOCI Attributable to Parent [Member] Operating lease liabilities, noncurrent Operating Lease, Liability, Noncurrent Entity Voluntary Filers Entity Voluntary Filers Passive Institutional Investor Passive Institutional Investor [Member] Passive Institutional Investor Milestone payments Milestone Payments Milestone payments. Fair Value as of Grant Date Award Grant Date Fair Value Entity Registrant Name Entity Registrant Name Retirement Plan Name Retirement Plan Name [Domain] Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Net operating loss (NOL) carryforwards Operating Loss Carryforwards Stock-based compensation expenses Employee Benefits and Share-Based Compensation Total salary / benefits Labor and Related Expense Summary of Long-term Debt Balance Schedule of Long-Term Debt Instruments [Table Text Block] Expected volatility Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate RSUs granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period RSUs forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Fair Value, Less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Maximum future payments upon achievement of certain development and commercial milestones Maximum Future Payments Upon Achievement Of Certain Development And Commercial Milestones Maximum future payments upon achievement of certain development and commercial milestones. Total Assets, Fair Value Disclosure Summary of Financial Information for Segment Segment, Reconciliation of Other Items from Segments to Consolidated [Table Text Block] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Interest receivable Interest Receivable, Current Counterparty Name Counterparty Name [Domain] Number of operating segments Number of Operating Segments Reverse stock split Stockholders' Equity Note, Stock Split, Conversion Ratio Amortization of premiums and discounts on marketable securities Accretion (Amortization) of Discounts and Premiums, Investments Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Weighted average remaining contractual term, (Years) Outstanding balance Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Increase in number of shares reserved for issuance as percentage of total number of shares of capital stock outstanding on last date of preceding calendar year Increase In Number Of Shares Reserved For Issuance As Percentage Of Total Number Of Shares Of Capital Stock Outstanding On Last Date Of Preceding Calendar Year Increase in number of shares reserved for issuance as percentage of total number of shares of capital stock outstanding on last date of preceding calendar year. Employer match of per contribution towards participants contribution Defined Contribution Plan Employer Match Of Per Contribution Towards Participants Contribution Defined contribution plan employer match of per contribution towards participants contribution. Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Assets Held for Sale Assets Held For Sale [Policy Text Block] Assets Held For Sale Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Restatement Determination Date: Restatement Determination Date [Axis] Impairment loss of property and equipment Loss on remeasurement of assets held for sale Impairment of Long-Lived Assets to be Disposed of Non-PEO NEO Non-PEO NEO [Member] Foreign Deferred Foreign Income Tax Expense (Benefit) Aggregate intrinsic value, Outstanding, beginning balance Aggregate intrinsic value, Outstanding, ending balance Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Allowance for credit losses on securities in unrealized loss position Debt Securities, Available-for-Sale, Allowance for Credit Loss Summary of Restructuring and Impairment Charges Restructuring and Related Costs [Table Text Block] Interest expense Interest Expense, Debt Everest License Agreement Everest License Agreement [Member] Everest License Agreement. 2015 Equity Incentive Plan Two Thousand Fifteen Equity Incentive Plan [Member] Two thousand fifteen equity incentive plan. Sale of Stock Sale of Stock [Axis] Unrealized Gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Name Trading Arrangement, Individual Name All Award Types Award Type [Domain] Less than 12 months Lessee, Operating Lease, Liability, to be Paid, Year One Equity Awards Adjustments Equity Awards Adjustments [Member] Leasehold improvements Leasehold Improvements [Member] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Compensation Amount Outstanding Recovery Compensation Amount Deferred: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Other protein secretion discovery programs Protein Secretion [Member] Protein Secretion Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Expected dividend yield Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] 2018 Plan Two Thousand Eighteen Plan [Member] Two thousand eighteen plan . Organization And Description Of Business [Line Items] Organization And Description Of Business [Line Items] Organization and description of business. MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Name Awards Close in Time to MNPI Disclosures, Individual Name Rate differential Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent Cash payments made Payments for Restructuring Outstanding, beginning balance (in usd per share) Outstanding, ending balance (in usd per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Restructuring Type [Axis] Restructuring Type [Axis] Australia AUSTRALIA Segment, Reconciliation of Other Items from Segments to Consolidated [Line Items] Segment, Reconciliation of Other Items from Segments to Consolidated [Line Items] Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] ESPP Rights Employee Stock [Member] ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Employer match of employees contributions in amount in percentage Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Lease Liabilities Deferred Tax Assets Lease Liability Deferred tax assets lease liability. Stock-based compensation expense APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Defined Contribution Plan Disclosure [Line Items] Defined Contribution Plan Disclosure [Line Items] Financial Instruments [Domain] Financial Instruments [Domain] Foreign Foreign Tax Jurisdiction [Member] Auditor Firm ID Auditor Firm ID Segments [Domain] Segments [Domain] Statement of Income Location, Balance Statement of Income Location, Balance [Axis] Foreign Income (Loss) from Continuing Operations before Income Taxes, Foreign Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Royalty Royalty [Member] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Other Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount Statement of Financial Position Location, Balance [Domain] Statement of Financial Position Location, Balance [Domain] Amortization of debt discount and issuance costs and other non-cash interest Amortization of Debt Issuance Costs and Discounts Pre funded warrants to purchase shares of common stock (in shares) Class of Warrant or Right, Number of Securities Called by Warrants or Rights Minimum Minimum [Member] Equal To Sum Of B Equal To Sum Of B [Member] Equal to the sum of (b). Less: accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Net Loss per Share Earnings Per Share, Policy [Policy Text Block] Company Selected Measure Name Company Selected Measure Name Number of lease options Number of Lease Options Number of Lease Options Debt Debt Disclosure [Text Block] Preferred stock, $0.001 par value, 10,000,000 shares authorized, zero shares issued and outstanding as of December 31, 2025 and 2024 Preferred Stock, Value, Issued Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Accounts payable Accounts Payable, Current Deferred tax liabilities Deferred Tax Liabilities, Net [Abstract] Defined Contribution Plan [Table] Defined Contribution Plan [Table] Cash paid for operating lease liabilities Operating Lease, Payments Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] All Executive Categories All Executive Categories [Member] Summary of Components of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] License Agreement License Agreement [Member] License agreement. Common stock, $0.001 par value, 250,000,000 shares authorized as of December 31, 2025 and 2024; 7,331,739 and 7,303,629 shares issued and outstanding as of December 31, 2025 and 2024, respectively Common Stock, Value, Issued Foreign Current Foreign Tax Expense (Benefit) Modified exercise price (in usd per share) Share Based Payment Arrangement Option Exercise Price Range Outstanding Modified Exercise Price Modified exercise price with respect to all outstanding stock options which are in the customized range of exercise prices. Expected volatility, Minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Commitments & Contingencies Commitments and Contingencies Disclosure [Text Block] Share-Based Payment Arrangement, Tranche Two Share-Based Payment Arrangement, Tranche Two [Member] Weighted-average shares used to compute net loss per common share, diluted (in shares) Weighted-average shares of common stock outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted No Trading Symbol Flag No Trading Symbol Flag Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Others Other Prepaid Expense, Current Entity Small Business Entity Small Business Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Interest charges or penalties related to unrecognized tax benefits Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding KZR-261 KZR-261 [Member] KZR-261 State Current State and Local Tax Expense (Benefit) Document Transition Report Document Transition Report Intercompany debt forgiveness - foreign subsidiary Effective Income Tax Rate Reconciliation, Nondeductible Expense, Intercompany Debt Forgiveness, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Intercompany Debt Forgiveness, Amount Reportable Segment Reportable Segment [Member] Reportable Segment Numerator: Net Income (Loss) Available to Common Stockholders, Basic [Abstract] Underlying Securities Award Underlying Securities Amount Net deferred tax assets Deferred Tax Assets, Net Equity Component Equity Component [Domain] Document Period End Date Document Period End Date PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Income Taxes Income Tax Disclosure [Text Block] Number of tranches Number of Tranches Number of tranches. Balance Sheet Components Supplemental Balance Sheet Disclosures [Text Block] Reclassification of cumulative currency translation loss to other expenses Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Tranche One Tranche One [Member] Tranche one. Summary of Reconciliation of Unrecognized Tax Benefits Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Reserves and accruals Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals Document Type Document Type Level 3 Fair Value, Inputs, Level 3 [Member] Net Loss Per Share Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Product and Service [Axis] Product and Service [Axis] Variable lease costs Variable Lease, Cost Collaboration revenue Revenue from Contract with Customer, Excluding Assessed Tax All Individuals All Individuals [Member] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Name Forgone Recovery, Individual Name Options granted expiry period Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period Total current assets Assets, Current Statistical Measurement Statistical Measurement [Axis] Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Stockholder Rights Plan Stockholder Rights Plan [Member] Stockholder Rights Plan Summary Of Significant Accounting Policies [Line Items] Summary Of Significant Accounting Policies [Line Items] Summary of significant accounting policies. Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Option price per share of common stock at fair market value Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent Right-of-use asset Deferred Tax Liabilities Right Of Use Asset Deferred tax liabilities right of use asset. Aggregate intrinsic value, options exercised Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value Summary of Other Assets Schedule of Other Assets [Table Text Block] Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Compensation expense related to the unvested option Share Based Compensation Expense Plan Modification Unamortized Incremental Compensation Cost of Unvested Option Shares Share based compensation expense plan modification unamortized incremental compensation cost of unvested option shares. Marketable securities Marketable Securities, Current Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Purchase price of shares upon rights exercise (usd per share) Purchase Price of Shares Upon Rights Exercise Purchase Price of Shares Upon Rights Exercise Total other comprehensive income (loss), net of tax Other comprehensive (loss) income Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Current liabilities: Liabilities, Current [Abstract] Research and development credit carryforwards Deferred Tax Assets, Tax Credit Carryforwards, Research Stock Options Additional Disclosures Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Additional Disclosures [Abstract] Geographical Geographical [Axis] Total operating expenses Operating Expenses Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Risk-free interest rate, Minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Level 1 Fair Value, Inputs, Level 1 [Member] Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Aggregate intrinsic value, options vested and exercisable Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Exercisable Intrinsic Value Sharebased compensation arrangement by sharebased payment award options vested and exercisable intrinsic value. Net loss per common share, diluted (in dollars per share) Net loss per common share, Diluted (in dollars per share) Earnings Per Share, Diluted Vested and exercisable (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Number Share based compensation arrangement by share based payment award options vested and exercisable number. Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Title of 12(b) Security Title of 12(b) Security Annual increase in number of common stock shares (in shares) Share Based Compensation Arrangement By Share Based Payment Award Annual Increase In Number Of Common Stock Shares Share based compensation arrangement by share based payment award annual increase in number of common stock shares. Insurance Prepaid Insurance Other comprehensive (loss) income, net of tax: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Earnings Per Share [Abstract] Earnings Per Share [Abstract] Operating lease asset and liabilities Increase (Decrease) in Operating Lease Asset and Liabilities Increase decrease in operating lease asset and liabilities. Organization and Description of the Business Business Description and Basis of Presentation [Text Block] Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Auditor Location Auditor Location Weighted average remaining contractual term, (Years) options vested and exercisable Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Exercisable Weighted Average Remaining Contractual Term Sharebased compensation arrangement by sharebased payment award options vested and exercisable weighted average remaining contractual term. Summary of Anti-dilutive Outstanding Shares of Common Stock Equivalents Excluded from Computation of Diluted Net Loss per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Tax credit carryforward Tax Credit Carryforward, Amount Final payment fee percentage Final Payment Fee Percentage on Principal Final payment fee percentage on principal. Segment, Reconciliation of Other Items from Segments to Consolidated [Table] Segment, Reconciliation of Other Items from Segments to Consolidated [Table] Federal Domestic Tax Jurisdiction [Member] Less: imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Tax Credit Carryforward Tax Credit Carryforward [Axis] Other Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Percent Options exercised (in usd per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Schedule Of Collaborative Arrangements And Noncollaborative Arrangement Transactions [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Award Timing Disclosures [Line Items] Noncurrent unbilled receivable from collaboration Noncurrent Unbilled Receivable From Collaboration Noncurrent Unbilled Receivable From Collaboration Options granted (in usd per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Accrued employee-related costs Employee-related Liabilities, Current Measurement Frequency Measurement Frequency [Domain] Look back period Share-Based Compensation Arrangement by Share-Based Payment Award, Look Back Period Share-Based Compensation Arrangement by Share-Based Payment Award, Look Back Period Total undiscounted lease payments Lessee, Operating Lease, Liability, to be Paid Operating lease, renewal term Lessee, Operating Lease, Renewal Term Net unrealized (loss) gain on marketable securities OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Stockholders' Equity Equity [Text Block] State Deferred State and Local Income Tax Expense (Benefit) Par value of common stock upon cashless exercise of prefunded warrants Par Value of Common Stock Upon Cashless Exercise of Prefunded Warrants Par value of common stock upon cashless exercise of prefunded warrants. Current borrowing capacity Line of Credit Facility, Current Borrowing Capacity Ownership percentage Beneficial Ownership Acquired Percentage Beneficial Ownership Acquired Percentage Net loss Net loss Net Income (Loss) Attributable to Parent Subsequent Event [Table] Subsequent Event [Table] Summary of Gross Unrealized Losses and Fair Value by Major Security Type for Available-For-Sale Securities in Unrealized Loss Position Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] Expiration Date Trading Arrangement Expiration Date Restructuring and Impairment Charges Restructuring, Impairment, and Other Activities Disclosure [Text Block] Others Other Accrued Liabilities, Current 2018 Employee Stock Purchase Plan Two Thousand Eighteen Employee Stock Purchase Plan [Member] Two thousand eighteen employee stock purchase plan. Summary of Effective Tax Rate Reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Restricted stock units subject to future vesting Restricted Stock Units Subject To Future Vesting [Member] Restricted Stock Units Subject To Future Vesting [Member] Option grant vesting period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Property and equipment, net Property and equipment, net Property, Plant and Equipment, Net Restructuring charges Restructuring Charges Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Adoption Date Trading Arrangement Adoption Date Floor Rate Base Rate [Member] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Zetomipzomib Zeto [Member] Zetomipzomib Restructuring Cost [Table] Restructuring Cost [Table] Proceeds from issuance of common stock under employee stock incentive plans Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Excluding Option Exercised Entity Current Reporting Status Entity Current Reporting Status Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Loss from operations Operating Income (Loss) Accumulated deficit Accumulated deficit Retained Earnings (Accumulated Deficit) External costs by program External Costs by Program [Abstract] External Costs by Program U.S federal statutory tax rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Loss on disposal of property and equipment Gain (Loss) on Disposition of Property Plant Equipment Financial Instrument [Axis] Financial Instrument [Axis] Issuance of common stock under employee stock incentive plans Issuance of Shares under Incentive and Share Based Compensation Plans, Value Value of issuance of shares under incentive and share based compensation plans. Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] 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] Executive Category: Executive Category [Axis] Stock-based compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Percent Repayments of debt Repayments of Debt State and local income taxes, net of federal income tax effect Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Incremental cost Share-Based Payment Arrangement, Plan Modification, Incremental Cost Current Fiscal Year End Date Current Fiscal Year End Date Class of Stock [Axis] Class of Stock [Axis] Percentage of employees contributions amount up to lesser of pre-tax compensation Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Subsequent Event Type [Domain] Subsequent Event Type [Domain] Expected term (years) Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term Unrealized Losses, Less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Shares granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant Statement [Table] Statement [Table] Benefit for deferred tax assets Total deferred Deferred Income Tax Expense (Benefit) 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] Everest Collaboration License Agreement Collaborative Arrangement Disclosure [Text Block] Cash flows from financing activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Permanent differences Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent Weighted average grant date fair value of options granted (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Development and commercial milestone amount to be received Development And Commercial Milestone Amount To Be Received Development And Commercial Milestone Amount To Be Received Contra research and development expense Contra Research and Development Expense Contra research and development expense. Variable Rate [Domain] Variable Rate [Domain] Liability related to uncertain tax positions Liability Related To Uncertain Tax Position Liability related to uncertain tax position. Maturities of marketable securities Proceeds from Sale and Maturity of Marketable Securities Unrecognized tax benefits Balance at the beginning of the year Balance at the end of the year Unrecognized Tax Benefits Anti-dilutive securities excluded from computation of diluted net loss per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Denominator: Weighted Average Number of Shares Outstanding, Diluted [Abstract] All Adjustments to Compensation All Adjustments to Compensation [Member] Amendment Flag Amendment Flag Maximum number of shares authorized available for issuance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized Marketable securities Marketable Securities [Member] Marketable Securities Lease Lessee, Operating Leases [Text Block] Termination Date Trading Arrangement Termination Date Net cash (used in) provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Licenses, dues and subscriptions Prepaid License Dues And Subscription, Current Prepaid license dues and subscription. Measure: Measure [Axis] Share-Based Payment Arrangement, Tranche Three Share-Based Payment Arrangement, Tranche Three [Member] Cashless exercise of pre-funded warrants (in shares) Stock Issued During Period, Cashless Exercise of Prefunded Warrants, Shares Stock issued during period shares cashless exercise of prefunded warrants. Operating lease liability, weighted average discount rate Operating Lease, Weighted Average Discount Rate, Percent Summary of Activity under Stock Option Plans and Related Information Share-Based Payment Arrangement, Option, Activity [Table Text Block] Accrued interest and penalties related to gross unrecognized tax benefits Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Long-Lived Tangible Asset Long-Lived Tangible Asset [Domain] Summary of Financial Assets Measured at Fair Value on a Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Weighted-average shares used to compute net loss per common share, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Table] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table] Summary of Calculation of Basic and Diluted Net Loss per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Maximum number of shares issued upon exercise of incentive stock options (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number Subsequent Events [Abstract] Segment Reporting [Abstract] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Risk-free interest rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Entity Tax Identification Number Entity Tax Identification Number Unbilled receivable from Everest, noncurrent (Note 10) Other Unbilled Receivable Other Unbilled Receivable Outstanding, beginning balance (in usd per share) Outstanding, ending balance (in usd per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Other Assets Other Assets Policy [Policy Text Block] Other assets policy. Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares issued (in shares) Common Stock, Shares, Issued Weighted average remaining lease term Operating Lease, Weighted Average Remaining Lease Term Options granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross Incentive Stock Options Incentive Stock Options [Member] Incentive stock options. Oxford Finance LLC Oxford Finance L L C [Member] Oxford finance LLC. Use of Estimates Use of Estimates, Policy [Policy Text Block] Vested and exercisable (in usd per share) Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Exercisable Weighted Average Exercise Price Share based compensation arrangement by share based payment award options vested and exercisable weighted average exercise price. Entity Public Float Entity Public Float Other expenses Interest Expense, Nonoperating Trading Arrangement: Trading Arrangement [Axis] Total Shareholder Return Amount Total Shareholder Return Amount Subsequent Event Subsequent Events [Text Block] Restructuring and impairment charges Restructuring charges Total Restructuring Costs and Asset Impairment Charges Insider Trading Arrangements [Line Items] Security Exchange Name Security Exchange Name Options cancelled/forfeited (in usd per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Total liabilities Liabilities Antidilutive Securities, Name Antidilutive Securities, Name [Domain] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Line of credit facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Increase related to current year tax positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Sufficient cash and cash equivalents available period term Sufficient Cash And Cash Equivalents Available Period Term Sufficient cash and cash equivalents available period term. Operating expenses: Operating Expenses [Abstract] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Accrued clinical costs Accrued Clinical Costs Current Accrued clinical costs, current. Line of credit facility, interest rate Line of Credit Facility, Interest Rate During Period Statement [Line Items] Statement [Line Items] Variable Rate [Axis] Variable Rate [Axis] Summary of Accrual Activity and Payments Relating to Restructuring and Impairment Charge Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Cash and cash equivalents Cash and Cash Equivalent Counterparty Name Counterparty Name [Axis] Summary of RSU Activity Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] Subsequent Event [Line Items] Subsequent Event [Line Items] Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Research and Development Research Tax Credit Carryforward [Member] Development Regulatory and Commercial Milestones Development Regulatory and Commercial Milestones [Member] Development regulatory and commercial milestones. Risk-free interest rate, Maximum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum Common Stock COMMON STOCK Common Stock [Member] RSUs vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Marketable securities Fair Value Debt securities, available for sale Debt Securities, Available-for-Sale Tax Credit Carryforward, Name Tax Credit Carryforward, Name [Domain] Summary of Prepaid Expenses and Other Current Assets Schedule Of Prepaid Expenses [Table Text Block] Tabular disclosure of prepaid expenses. Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Corporate debt securities Corporate Debt Securities [Member] Available-for-Sale Securities Available For Sale Securities Disclosure [Text Block] The entire disclosure for available for sale securities. Net increase (decrease) in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Accrued professional services Accrued Professional Fees, Current