Series A Series A Preferred Stock [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Leases Lessee, Leases [Policy Text Block] Stock-based compensation expense APIC, Share-based Payment Arrangement, Increase for Cost Recognition Summary of Convertible Preferred Stock Temporary Equity [Table Text Block] Total current liabilities Liabilities, Current Other prepaid expenses and current assets Other Prepaid Expense, Current Variable Interest Entity, Classification [Domain] Variable Interest Entity, Classification [Domain] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Other assets Increase (Decrease) in Other Noncurrent Assets Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Recently Adopted Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Vested (in shares) Restricted common stock vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Current Fiscal Year End Date Current Fiscal Year End Date Free rent period Lessee, Operating Lease, Free Rent Period Lessee, Operating Lease, Free Rent Period Maximum milestone payments for licensed products Research and Development Arrangement, Contract to Perform for Others. 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administrative General and Administrative Expense [Member] Ownership percentage of VIE Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage Restricted stock Restricted stock subject to future vesting Restricted Stock [Member] Current liabilities: Liabilities, Current [Abstract] Right-of-use asset obtained in exchange for lease liability Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Price per share (in USD per share) Stock Purchase Agreement, Price Per Share Stock Purchase Agreement, Price Per Share Increase in shares available for grant, percentage of shares outstanding Share-based Compensation Arrangement by Share-based Payment Award, Increase In Number Of Shares Available For Grant, Percentage Of Shares Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Increase In Number Of Shares Available For Grant, Percentage Of Shares Outstanding Property, Plant and Equipment, Type [Domain] Property, Plant and 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Hawkeye Hawkeye [Member] Hawkeye Statement [Line Items] Statement [Line Items] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Fair Value Disclosures [Abstract] Prepaid clinical trial costs Prepaid Clinical Trial Test Costs, Current Prepaid Clinical Trial Test Costs, Current Intrinsic value of options exercised during the period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Beginning balance, weighted-average exercise price (in USD per share) Ending balance, weighted-average exercise price (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Net Loss Per Share Earnings Per Share, Policy [Policy Text Block] Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Plan Name [Axis] Plan Name [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Schedule of 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[Member] Current assets: Assets, Current [Abstract] Number of tranches (in tranches) Stock Purchase Agreement, Number of Tranches Stock Purchase Agreement, Number of Tranches Series B Series B Preferred Stock [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Lease Description [Domain] Lease Description [Domain] Lease Description Stock Purchase Agreement, Tranche One Stock Purchase Agreement, Tranche One [Member] Stock Purchase Agreement, Tranche One Entity Small Business Entity Small Business Commitments and Contingencies Disclosure [Abstract] Schedule of Research and Development Arrangement, Contract to Perform for Others [Table] Schedule of Research and Development Arrangement, Contract to Perform for Others [Table] Entity Filer Category Entity Filer Category Deferred financing costs included in accounts payable and accrued liabilities Deferred Financing Costs Incurred But Not Yet Paid Deferred Financing Costs Incurred But Not Yet Paid Accrued expenses and other current liabilities Other Accrued Liabilities, Current Stock-based compensation expense Share-based Payment Arrangement, Expense Total liabilities, convertible preferred stock and stockholders’ equity (deficit) Liabilities and Equity Conversion of preferred stock into common stock upon initial public offering (in shares) Shares issued as a result of conversion of promissory notes (in shares) Stock Issued During Period, Shares, Conversion of Convertible Securities Entity Address, City or Town Entity Address, City or Town Balance Sheet Components Supplemental Balance Sheet Disclosures [Text Block] Operating lease liability, noncurrent Operating Lease, Liability, Noncurrent Variable Interest Entities [Axis] Variable Interest Entities [Axis] Operating expenses: Operating Expenses [Abstract] Collaboration agreement, threshold of proceeds from stock issuance for additional consideration 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Temporary Equity, Value, Conversion Of Convertible Securities Class of Stock [Line Items] Class of Stock [Line Items] Subsequent Events [Abstract] Early exercise liability Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent Options issued and outstanding Stock Options Issued and Outstanding [Member] Stock Options Issued and Outstanding Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Cash paid for amounts included in the measurement of lease liabilities Operating Lease, Payments Number of shares vesting on a monthly basis (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Vesting On A Monthly Basis Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Vesting On A Monthly Basis Square footage of leased space Lessee, Operating Lease, Square Footage Of Leased Space Lessee, Operating Lease, Square Footage Of Leased Space Common stock awards available for grant under employee benefit plans Stock Awards, Future Grant [Member] Stock Awards, Future Grant Preferred stock issued Temporary Equity, Stock Issued During Period, Value, New Issues Accumulated Deficit Retained Earnings [Member] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event [Line Items] Subsequent Event [Line Items] Shares of restricted stock issued to founders (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period Collaborative arrangement, numerator for determining additional consideration Collaborative Arrangement, Numerator For Determining Additional Consideration Collaborative Arrangement, Numerator For Determining Additional Consideration Document Period End Date Document Period End Date Statement [Table] Statement [Table] Entity Registrant Name Entity Registrant Name Purchases of marketable securities Payments to Acquire Debt Securities, Available-for-sale Temporary Equity, by Class of Stock [Table] Temporary Equity, by Class of Stock [Table] Based number of options issuable (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Base Number Of Options Issuable Share-based Compensation Arrangement by Share-based Payment Award, Base Number Of Options Issuable CASH FLOWS FROM INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities [Abstract] Maximum Maximum [Member] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] 2020 Equity Incentive Plan 2020 Equity Incentive Plan [Member] 2020 Equity Incentive Plan Number of operating leases (in leases) Lessee, Operating Leases, Number Facilities Leased Lessee, Operating Leases, Number Facilities Leased Restricted Stock Unit Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Remaining Contractual Term (Years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Estimated fair value Debt Securities, Available-for-sale Right-of-use asset amortization Operating Lease, Right-of-Use Asset, Amortization Expense Operating Lease, Right-of-Use Asset, Amortization Expense Convertible preferred stock, $0.0001 par value; no shares and 48,787,898 shares authorized at March 31, 2020 and December 31, 2019, respectively; no shares and 24,385,388 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively Beginning Balance Ending Balance Net Carrying Value Temporary Equity, Carrying Amount, Attributable to Parent Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Accumulated deficit Accumulated deficit Retained Earnings (Accumulated Deficit) Convertible preferred stock outstanding Convertible preferred stock on an as-converted basis Convertible Preferred Stock [Member] Early exercise liability, current Deferred Compensation Share-based Arrangements, Liability, Current Entity Tax Identification Number Entity Tax Identification Number Outstanding principal amount Debt Instrument, Face Amount Purchase price per share (in USD per share) Temporary Equity, Stock Issued During Period, Price Per Share Temporary Equity, Stock Issued During Period, Price Per Share Unrealized gain on marketable securities Unrealized gain on short term investments Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax Trading Symbol Trading Symbol Minimum Minimum [Member] Marketable Securities Marketable Securities, Policy [Policy Text Block] Operating lease liabilities Increase (Decrease) in Operating Lease Liabilities Increase (Decrease) in Operating Lease Liabilities Legal Entity [Axis] Legal Entity [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Adjustments to reconcile net loss to net cash used in operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Stock Option Activity Share-based Payment Arrangement, Option, Activity [Table Text Block] Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Intrinsic value, exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Expected dividend yield Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Entity [Domain] Entity [Domain] Stock-Based Compensation Share-based Payment Arrangement [Text Block] Number of shares issuable (in shares) Stock Purchase Agreement, Number Of Shares Issuable Stock Purchase Agreement, Number Of Shares Issuable Vesting [Axis] Vesting [Axis] 2021 Lessee, Operating Lease, Liability, Payments, Due Year Two Subsidiary, Sale of Stock [Line Items] Subsidiary, Sale of Stock [Line Items] Other long-term liabilities Other Liabilities, Noncurrent City Area Code City Area Code Risk-free interest rate, minimum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Stock Purchase Agreement, Tranche Three Stock Purchase Agreement, Tranche Three [Member] Stock Purchase Agreement, Tranche Three Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Title of 12(b) Security Title of 12(b) Security Vesting of founder shares subject to repurchase Stock Issued During Period, Vesting Of Founder Shares Subject To Repurchase, Value Stock Issued During Period, Vesting Of Founder Shares Subject To Repurchase, Value Exercisable, Weighted-Average Exercise Price (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Early exercise liability, noncurrent Deferred Compensation Share-based Arrangements, Liability, Classified, Noncurrent Total assets Assets, Fair Value Disclosure Common stock reserved (in shares) Common Stock, Capital Shares Reserved for Future Issuance Earnings Per Share [Abstract] Counterparty Name [Axis] Counterparty Name [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Operating Lease Payments Lessee, Operating Lease, Liability, Maturity [Table Text Block] Granted (in USD 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 ASSETS Assets [Abstract] Unrealized gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Series C Series C Preferred Stock [Member] Beginning Balance, shares Ending Balance, shares Shares, Outstanding Preferred stock, par value (in USD per share) Preferred Stock, Par or Stated Value Per Share Entity Ex Transition Period Entity Ex Transition Period Number of operating segments (segment) Number of Operating Segments Weighted-average remaining lease term (in years) Operating Lease, Weighted Average Remaining Lease Term Maximum milestone payments for net worldwide sales Research and Development Arrangement, Contract to Perform for Others, Maximum Sales Milestone Payments Research and Development Arrangement, Contract to Perform for Others, Maximum Sales Milestone Payments Reverse stock split ratio for capital stock Stockholders' Equity Note, Stock Split, Conversion Ratio Proceeds from issuance of convertible preferred stock Proceeds from Issuance of Convertible Preferred Stock Prepaid insurance Prepaid Insurance CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Total operating expenses Operating Expenses AstraZeneca 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Current Clinical Trial Accrual, Current Weighted-average discount rate Operating Lease, Weighted Average Discount Rate, Percent Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Number of Options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Schedule of Prepaid Expenses and Other Current Assets Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block] Accounts payable Increase (Decrease) in Accounts Payable Statement of Financial Position [Abstract] Expected volatility, minimum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Performance Condition Restricted Stock Performance Condition Restricted Stock [Member] Performance Condition Restricted Stock Variable lease payments Variable Lease, Cost Preferred stock issued (in shares) Temporary Equity, Stock Issued During Period, Shares, New Issues Temporary Equity, Stock Issued During Period, Shares, New Issues Emerging Growth Company Status Emerging Growth Company Status [Policy Text Block] Emerging Growth Company Status Common stock, shares authorized (in shares) Common Stock, Shares Authorized Statement of Cash Flows [Abstract] Entity Central Index Key Entity Central Index Key Convertible preferred stock, shares authorized (in shares) Temporary Equity, Shares Authorized Unvested restricted stock (in shares) Beginning balance (in shares) Ending balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Entity Emerging Growth Company Entity Emerging Growth Company Sale of Stock [Domain] Sale of Stock [Domain] Stock-based compensation Share-based Payment Arrangement, Noncash Expense Operating lease liability Current portion operating lease liability Operating Lease, Liability, Current Income Taxes Income Tax, Policy [Policy Text Block] Stock issuance costs Payments of Stock Issuance Costs Accrued compensation Employee-related Liabilities, Current 2020 (April through December) Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year Level 2 Fair Value, Inputs, Level 2 [Member] Lease term (in months) Lessee, Operating Lease, Term of Contract Antidilutive Securities [Axis] Antidilutive Securities [Axis] Building Building [Member] Lease Description [Axis] Lease Description [Axis] Lease Description Fair Value Measurement Fair Value Measurement, Policy [Policy Text Block] Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Research and Development Research and Development Expense, Policy [Policy Text Block] LIABILITIES, CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ EQUITY (DEFICIT) Liabilities and Equity [Abstract] Other assets Other Assets, Noncurrent CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Underwriters' option Over-Allotment Option [Member] Segments Segment Reporting, Policy [Policy Text Block] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Variable Interest Entity, Not Primary Beneficiary Variable Interest Entity, Not Primary Beneficiary [Member] Sale of Stock [Axis] Sale of Stock [Axis] Vested (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value Subsequent Event [Table] Subsequent Event [Table] Recognition period for unrecognized compensation costs related to unvested options expected to vest Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Accounting Policies [Abstract] Liquidation Preference Temporary Equity, Liquidation Preference Additional Paid-In Capital Additional Paid-in Capital [Member] Stock-Based Compensation Share-based Payment Arrangement [Policy Text Block] Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table] Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table] Cash and Cash Equivalents [Line Items] Cash and Cash Equivalents [Line Items] Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Straight-line rent expense Lessee, Operating Lease, Monthly Rent Expense Lessee, Operating Lease, Monthly Rent Expense Cash and cash equivalents and debt securities, available for sale Cash And Cash Equivalents And Debt Securities, Available For Sale, Fair Value Disclosure Cash And Cash Equivalents And Debt Securities, Available For Sale, Fair Value Disclosure Increase (Decrease) in Temporary Equity [Roll Forward] Increase (Decrease) in Temporary Equity [Roll Forward] Purchase price of common stock, as a percentage of closing trading price per share Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Payments, milestones or royalties Research And Development Arrangement, Payments, Milestones, Or Royalties Research And Development Arrangement, Payments, Milestones, Or Royalties Deferred financing costs Debt Issuance Costs, Current, Net Entity Address, State or Province Entity Address, State or Province Income Statement Location [Axis] Income Statement Location [Axis] IPO IPO [Member] First anniversary date Share-based Payment Arrangement, Tranche One [Member] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Convertible Preferred Stock Stockholders' Equity Note, Redeemable Preferred Stock, Issue, Policy [Policy Text Block] Monthly basis Share-based Payment Arrangement, Tranche Two [Member] Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Cash, cash equivalents, and marketable securities Cash, Cash Equivalents, and Short-term Investments General and administrative General and Administrative Expense Accounts payable Accounts Payable, Current Accrued liabilities Total accrued liabilities Accrued Liabilities, Current Entity Interactive Data Current Entity Interactive Data Current Westlake Village, California Lease Arrangement Westlake Village, California Lease Arrangement [Member] Westlake Village, California Lease Arrangement Common stock, shares, issued (in shares) Common Stock, Shares, Issued Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Common stock, par value (in USD per share) Common Stock, Par or Stated Value Per Share Antidilutive 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termination option Lessee, Operating Lease, Term For Termination Option Lessee, Operating Lease, Term For Termination Option Shares available for grant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Award Type [Domain] Award Type [Domain] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Granted (in USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Stock Purchase Agreement, Tranche Two Stock Purchase Agreement, Tranche Two [Member] Stock Purchase Agreement, Tranche Two Issuance of shares of common stock, net of issuance costs (in shares) Stock Issued During Period, Shares, New Issues Vesting percentage Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Restricted stock units outstanding Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Research and development Research and Development Expense [Member] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] 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] Lapse of repurchase rights related to common stock issued pursuant to early exercises (in shares) Stock Issued During Period, Lapse of Repurchase Rights Related to Common Stock Issued Pursuant to Early Exercises, Shares Stock Issued During Period, Lapse of Repurchase Rights Related to Common Stock Issued Pursuant to Early Exercises, Shares Total liabilities Liabilities Common stock, $0.0001 par value; 300,000,000 and 65,820,000 shares authorized at March 31, 2020 and December 31, 2019, respectively; 38,154,550 and 2,879,763 shares issued at March 31, 2020 and December 31, 2019, respectively; 37,471,997 and 2,120,853 shares outstanding at March 31, 2020 and December 31, 2019, respectively Common Stock, Value, Issued Proceeds from maturities of marketable securities Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Research and development Research and Development Expense Early exercised options subject to future vesting Early Exercised Options [Member] Early Exercised Options Vesting [Domain] Vesting [Domain] Counterparty Name [Domain] Counterparty Name [Domain] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Schedule of Cash and Cash Equivalents [Table] Schedule of Cash and Cash Equivalents [Table] Debt Securities, Available-for-sale, Allowance for Credit Loss Debt Securities, Available-for-sale, Allowance for Credit Loss Expected volatility, maximum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value License Agreements Collaborative Arrangement Disclosure [Text Block] Operating lease right-of-use asset Operating Lease, Right-of-Use Asset Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Equity Components [Axis] Equity Components [Axis] Weighted-Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Total stockholders’ equity (deficit) Beginning Balance Ending Balance Stockholders' Equity Attributable to Parent Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Grant date fair value of options vested during the period Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value Net amortization/accretion on marketable securities Accretion (Amortization) of Discounts and Premiums, Investments Convertible Debt Convertible Debt [Member] Fair Value Measurements Fair Value Disclosures [Text Block] Tenant improvement allowance Lessee, Operating Lease, Tenant Improvement Allowance Lessee, Operating Lease, Tenant Improvement Allowance Operating Lease Supplemental Cash Flow Information Lease, Cost [Table Text Block] Conversion of preferred stock into common stock upon initial public offering Stock Issued During Period, Value, Conversion of Convertible Securities Preferred stock, $0.0001 par value; 10,000,000 and no shares authorized at March 31, 2020 and December 31, 2019, respectively; no shares issued and outstanding at March 31, 2020 and December 31, 2019; Preferred Stock, Value, Issued Convertible preferred stock, shares outstanding (in shares) Beginning balance, convertible preferred stock (in shares) Ending balance, convertible preferred stock (in shares) Temporary Equity, Shares Outstanding Cash and cash equivalents Cash and cash equivalents, estimated fair value Cash and Cash Equivalents, Fair Value Disclosure Security Exchange Name Security Exchange Name Potentially antidilutive shares excluded from the calculation of net loss per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Depreciation Depreciation Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Marketable securities Debt Securities, Available-for-sale, Current Net cash used in operating activities Net Cash Provided by (Used in) Operating Activities Number of Units Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Equity Component [Domain] Equity Component [Domain] Votes per share of common stock Common Stock, Voting Rights, Number Of Votes Per Share Common Stock, Voting Rights, Number Of Votes Per Share Expected term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Document Transition Report Document Transition Report Stock Options Stock options to purchase common stock Share-based Payment Arrangement, Option [Member] Employee Stock Purchase Plan ESPP shares subject to future issuance Employee Stock [Member] Government securities US Government Corporations and Agencies Securities [Member]