v3.19.3.a.u2
Net Loss per Share - Numerators and Denominators of Basic and Diluted Net Loss per Share Computations for Common Stock (Parenthetical) (Details) - IPO - shares
shares in Millions
1 Months Ended 12 Months Ended
Mar. 31, 2017
Dec. 31, 2019
Class B Common Stock | Series A, A-1, B, and C Preferred Stock    
Earnings Per Share [Line Items]    
Conversion of convertible preferred stock into common stock   163.0
Class C Common Stock | Series FP Preferred Stock    
Earnings Per Share [Line Items]    
Conversion of convertible preferred stock into common stock 215.9  
Class C Common Stock | Series FP Preferred Stock | Restricted Stock Units    
Earnings Per Share [Line Items]    
Conversion of convertible preferred stock into common stock   37.4
Class A Common Stock    
Earnings Per Share [Line Items]    
Common stock, shares issued 160.3 160.3