General form of registration statement for all companies including face-amount certificate companies

CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY - Convertible Preferred Stock Classes (Details)

v3.20.4
CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY - Convertible Preferred Stock Classes (Details) - USD ($)
Sep. 30, 2020
Dec. 31, 2019
Dec. 31, 2018
Class of Stock [Line Items]      
Convertible Preferred Stock, Outstanding 100,038,109 100,038,109  
Total $ 436,533,000 $ 436,533,000 $ 276,889,000
Series A Preferred Stock      
Class of Stock [Line Items]      
Convertible Preferred Stock, par value $ 0.0001 $ 0.0001  
Convertible Preferred Stock, Authorized 26,189,545 26,189,545 26,189,545
Convertible Preferred Stock, Issued 26,189,545 26,189,545 26,189,545
Convertible Preferred Stock, Outstanding 26,189,545 26,189,545  
Convertible Preferred Stock, Liquidation preference $ 255,348 $ 106,853,000 $ 88,783,000
Total 13,878,000 13,878,000 $ 13,878,000
Series B Preferred Stock      
Class of Stock [Line Items]      
Convertible Preferred Stock, par value $ 0.0001 $ 0.0001  
Convertible Preferred Stock, Authorized 23,675,035 23,675,035 23,675,035
Convertible Preferred Stock, Issued 23,675,035 23,675,035 23,675,035
Convertible Preferred Stock, Outstanding 23,675,035 23,675,035  
Convertible Preferred Stock, Liquidation preference $ 230,832,000 $ 96,594,000 $ 80,258,000
Total 37,806,000 37,806,000 $ 37,806,000
Series C Preferred Stock      
Class of Stock [Line Items]      
Convertible Preferred Stock, par value $ 0.0001 $ 0.0001  
Convertible Preferred Stock, Authorized   13,152,896 13,152,896
Convertible Preferred Stock, Issued 13,152,896 13,152,896 13,152,896
Convertible Preferred Stock, Outstanding 13,152,896 13,152,896  
Convertible Preferred Stock, Liquidation preference $ 128,241,000 $ 53,664,000 $ 45,000,000
Total 44,852,000 44,852,000 $ 44,852,000
Series D Preferred Stock      
Class of Stock [Line Items]      
Convertible Preferred Stock, par value $ 0.0001 $ 0.0001  
Convertible Preferred Stock, Authorized 21,075,193 21,075,193 21,075,193
Convertible Preferred Stock, Issued 21,075,193 21,075,193 21,075,193
Convertible Preferred Stock, Outstanding 21,075,193 21,075,193  
Convertible Preferred Stock, Liquidation preference $ 205,483,000 $ 180,522,000 $ 180,522,000
Total 180,353,000 180,353,000 $ 180,353,000
Series E Preferred Stock      
Class of Stock [Line Items]      
Convertible Preferred Stock, par value $ 0.0001 $ 0.0001  
Convertible Preferred Stock, Authorized 13,450,703 13,450,703 13,450,703
Convertible Preferred Stock, Issued 13,450,703 13,450,703 0
Convertible Preferred Stock, Outstanding 13,450,703 13,450,703 0
Convertible Preferred Stock, Liquidation preference $ 134,791,000 $ 134,791,000 $ 0
Total 134,667,000 134,667,000  
Series E1 Preferred Stock      
Class of Stock [Line Items]      
Convertible Preferred Stock, par value $ 0.0001 $ 0.0001  
Convertible Preferred Stock, Authorized 2,494,737 2,494,737 2,494,737
Convertible Preferred Stock, Issued 2,494,737 2,494,737 0
Convertible Preferred Stock, Outstanding 2,494,737 2,494,737 0
Convertible Preferred Stock, Liquidation preference $ 25,000,000 $ 25,000,000 $ 0
Total $ 24,977,000 $ 24,977,000