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Fair Value Measurements - Summary of Fair Value Assumptions (Details) - Convertible Preferred Stock Liability - Black Scholes Option Pricing Model
 12 Months Ended
Dec. 31, 2019
$ / shares
Stock Price | Minimum  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]  
Fair Measurement Input 0.99
Stock Price | Maximum  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]  
Fair Measurement Input 2.57
Exercise Price  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]  
Fair Measurement Input 1.00
Expected Term (Years) | Minimum  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]  
Fair Measurement Input 0 years
Expected Term (Years) | Maximum  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]  
Fair Measurement Input 2 years 2 months 30 days
Expected Volatility  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]  
Fair Measurement Input 72.0
Risk-free Interest Rate | Minimum  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]  
Fair Measurement Input 0.0
Risk-free Interest Rate | Maximum  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]  
Fair Measurement Input 2.4