v3.19.3.a.u2

Stockholder's Equity - Summary of Assumptions Used to Value Convertible Preferred Stock Warrants (Details) - Convertible Preferred Stock Warrants | Dec. 31, 2017
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Minimum | Expected term (in years) |
Class Of Warrant Or Right [Line Items] |
Fair value assumptions term | 3 years
Minimum | Risk-free interest rate |
Class Of Warrant Or Right [Line Items] |
Fair value assumptions | 1.5
Minimum | Expected volatility |
Class Of Warrant Or Right [Line Items] |
Fair value assumptions | 44
Maximum | Expected term (in years) |
Class Of Warrant Or Right [Line Items] |
Fair value assumptions term | 9 years 8 months 12 days
Maximum | Risk-free interest rate |
Class Of Warrant Or Right [Line Items] |
Fair value assumptions | 2.3
Maximum | Expected volatility |
Class Of Warrant Or Right [Line Items] |
Fair value assumptions | 51

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