Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Convertible Preferred Shares - Additional Information (Detail)

v3.21.1
Convertible Preferred Shares - Additional Information (Detail) - USD ($)
4 Months Ended 12 Months Ended
Dec. 10, 2020
Oct. 01, 2020
Feb. 24, 2019
Feb. 01, 2019
Jul. 01, 2019
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Mar. 01, 2019
Jan. 01, 2019
Temporary Equity [Line Items]                    
Proceeds from Issuance of convertible preferred shares, net of issuance expenses           $ 8,934,000 $ 161,233,000 $ 0    
Series A Convertible Preferred Shares [Member]                    
Temporary Equity [Line Items]                    
Temporary equity original issue price                   $ 0.4408
Temporary equity rate of interest on dividend declared but unpaid             6.00%      
Series B Convertible Preferred Shares [Member]                    
Temporary Equity [Line Items]                    
Temporary equity original issue price                   4.6366
Temporary equity rate of interest on dividend declared but unpaid             6.00%      
Series B-1 Convertible Preferred Shares [Member]                    
Temporary Equity [Line Items]                    
Temporary equity original issue price                   3.7093
Temporary equity rate of interest on dividend declared but unpaid             6.00%      
Series C Convertible Preferred Shares [Member]                    
Temporary Equity [Line Items]                    
Temporary equity original issue price                   $ 5.9842
Temporary equity redemption period       6 years            
Temporary equity shares issued durng the period new issues             28,216,005      
Temporary equity issuance costs     $ 4,730,000              
Series C Convertible Preferred Shares [Member] | Inital Series C Redeemable Preferred Shares Financing Round [Member]                    
Temporary Equity [Line Items]                    
Proceeds from Issuance of convertible preferred shares, net of issuance expenses     $ 102,850,000              
Temporary equity shares issued durng the period new issues     17,186,944              
Temporary equity issuance costs     $ 5,984.2              
Series C Convertible Preferred Shares [Member] | Muliple Deferred Closings [Member]                    
Temporary Equity [Line Items]                    
Temporary equity original issue price                 $ 5.9842  
Proceeds from Issuance of convertible preferred shares, net of issuance expenses         $ 66,000,000          
Temporary equity shares issued durng the period new issues         11,029,055          
Temporary equity issuance costs         $ 2,887,000          
Series C Convertible Preferred Shares [Member] | Minimum [Member]                    
Temporary Equity [Line Items]                    
Sale of stock minimum issue price as a percentage of issue price of redeemable convertible preferred stock                   200.00%
Proceeds from Issuance of convertible preferred shares, net of issuance expenses             $ 100,000,000      
Series C-1 Convertible Preferred Shares [Member]                    
Temporary Equity [Line Items]                    
Temporary equity original issue price   $ 9.573               $ 9.573
Proceeds from Issuance of convertible preferred shares, net of issuance expenses   $ 8,934,000                
Temporary equity rate of interest on dividend declared but unpaid             6.00%      
Temporary equity redemption period       6 years            
Temporary equity shares issued durng the period new issues   943,148       2,699,114        
Temporary equity issuance costs   $ 95,000                
Temporary equity price per share of issue predetermined           $ 6.583        
Premoney evaluation           $ 1,300,000,000        
Temporary equity predetermined issue price as a percentage of original issue price           70.00%        
Series C-1 Convertible Preferred Shares [Member] | Magna [Member]                    
Temporary Equity [Line Items]                    
Proceeds from Issuance of convertible preferred shares, net of issuance expenses $ 0                  
Temporary equity shares issued durng the period new issues 1,755,966