Reverse Capitalization - Summary of Retroactive Application of Reverse Capitalization to Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders' Deficit (Detail)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
shares
Dec. 31, 2019
shares
Dec. 31, 2018
USD ($)
shares
Mar. 31, 2021
shares
Retroactive Application of Reverse Capitalization to Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders Deficit [Line Items]        
Preferred stock, shares outstanding 139,444,346 139,444,346   0
Conversion ratio 2.0681 2.0681    
Common Stock [Member]        
Retroactive Application of Reverse Capitalization to Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders Deficit [Line Items]        
Common stock - shares     87,362,592  
Common stock - amount | $     $ 9  
Conversion ratio     2.0681  
Cumulative Preferred Stock [Member]        
Retroactive Application of Reverse Capitalization to Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders Deficit [Line Items]        
Preferred stock, shares outstanding     139,444,346  
Conversion ratio     2.0681  
Previously Reported [Member]        
Retroactive Application of Reverse Capitalization to Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders Deficit [Line Items]        
Preferred stock, shares outstanding 67,427,138 67,427,138    
Previously Reported [Member] | Common Stock [Member]        
Retroactive Application of Reverse Capitalization to Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders Deficit [Line Items]        
Common stock - shares     42,243,445  
Common stock - amount | $     $ 4  
Previously Reported [Member] | Cumulative Preferred Stock [Member]        
Retroactive Application of Reverse Capitalization to Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders Deficit [Line Items]        
Preferred stock, shares outstanding     67,427,138