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Commitments And Contingencies Disclosure [Line Items] Commitments And Contingencies Disclosure [Line Items] Commitments and contingencies disclosure. Common Stock Common Stock [Member] Foreign Foreign Tax Authority [Member] Issuance of common stock under Open Market Agreement, net of issuance costs Stock Issued During Period Value Issuance Of Under Open Market Agreement Stock issued during period value issuance of under open market agreement. Individual: Individual [Axis] 2019 Employee Stock Purchase Plan Two Thousand Nineteen Employee Stock Purchase Plan [Member] Two thousand nineteen employee stock purchase plan. 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Issuance of common stock under offering, net of issuance costs Stock Issued During Period, Value, New Issues Lease liability Deferred Tax Asset, Lease Liability Deferred Tax Asset, Lease Liability Equity [Abstract] Equity [Abstract] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Related party revenue Revenue from Contract with Customer, Excluding Assessed Tax Entity [Domain] Entity [Domain] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Amendment Flag Amendment Flag Income Tax Disclosure [Table] Income Tax Disclosure [Table] Income tax disclosure. 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