Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

v3.21.2
Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 1 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Aug. 16, 2021
Feb. 28, 2021
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
Dec. 31, 2019
Accounting Policies [Line Items]                
Net loss     $ (32,701) $ (7,624) $ (79,261) $ (22,340)    
Net Cash used in operating activities         40,008 8,420    
Cash and cash equivalents at carrying value     245,770   245,770      
Capitalized merger related costs     3,871   3,871   $ 0  
Related party transaction, Notes payable non current     $ 0   $ 0   7,498  
Net proceeds from merger transaction $ 236,632              
Common Stock, Par or Stated Value Per Share     $ 0.0001   $ 0.0001      
Class of Warrant or Right, Exercise Price of Warrants or Rights     $ 11.50   $ 11.50      
Public Warrants [Member]                
Accounting Policies [Line Items]                
Class of warrants or right issued during the period         11,499,992      
Private Placement Warrants [Member]                
Accounting Policies [Line Items]                
Class of warrants or right issued during the period         6,600,000      
One Of The Stockholders And Debtors WhoIs Also A Customer [Member]                
Accounting Policies [Line Items]                
Revenue from related party         $ 0 606    
Stockholder [Member]                
Accounting Policies [Line Items]                
Related party transaction, Notes payable non current     $ 0   0   $ 7,498  
Stockholder [Member] | Borrowed Convertible Notes Payable [Member] | Convertible Debt [Member]                
Accounting Policies [Line Items]                
Proceeds from related party debt   $ 1,232           $ 6,414
Related party transaction, Interest expenses     $ 89 $ 139 413 405    
General and Administrative Expense [Member]                
Accounting Policies [Line Items]                
Non cash merger related costs         6,591 $ 0    
Professional fees         4,846      
Other merger related costs         $ 1,745      
Accounts Receivable [Member] | Customer Concentration Risk [Member]                
Accounting Policies [Line Items]                
Concentration risk percentage             67.00%  
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer A [Member]                
Accounting Policies [Line Items]                
Concentration risk percentage         21.00%      
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer B [Member]                
Accounting Policies [Line Items]                
Concentration risk percentage         19.00%      
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer C [Member]                
Accounting Policies [Line Items]                
Concentration risk percentage         12.00%      
Maximum [Member]                
Accounting Policies [Line Items]                
Investments, Maturity terms         3 months