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volatility, maximum Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Organization and Description of Business Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Proceeds from initial public offering, net of issuance costs Proceeds from Issuance Initial Public Offering Additional paid-in capital Additional Paid in Capital Class of Stock [Axis] Class of Stock [Axis] Restricted Stock Unit Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Cash, cash equivalents, and restricted cash at beginning of period Cash, cash equivalents, and restricted cash at end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Accrued liabilities Total accrued liabilities Accrued Liabilities, Current Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Local Phone Number Local Phone Number Beginning balance, convertible preferred stock (in shares) Ending balance, convertible preferred stock (in shares) Convertible preferred stock, shares outstanding (in shares) Temporary Equity, Shares Outstanding First anniversary date Share-based Payment Arrangement, Tranche One [Member] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Intrinsic value of options exercised during the period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Depreciation Depreciation Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Tenant improvement allowance Lessee, Operating Lease, Tenant Improvement Allowance Lessee, Operating Lease, Tenant Improvement Allowance Entity Emerging Growth Company Entity Emerging Growth Company Issuance of shares of common stock upon the exercise of stock options Stock Issued During Period, Value, Stock Options Exercised Award Type [Axis] Award Type [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] Lease Contractual Term [Domain] Lease Contractual Term [Domain] Maximum Maximum [Member] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Fifth Anniversary Fifth Anniversary [Member] Fifth Anniversary Accumulated Deficit Retained Earnings [Member] Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding 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] Net cash provided by (used in) investing activities Net Cash Provided by (Used in) Investing Activities 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] Remaining Contractual Term (Years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Domain] Award Type [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 Trading Symbol Trading Symbol Exercisable, Weighted-Average Exercise Price (in USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, 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