Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Changes in Fair Value of Level 3 Financial Instruments (Details)

v3.21.2
Fair Value Measurements - Changes in Fair Value of Level 3 Financial Instruments (Details) - USD ($)
$ in Thousands
9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
Dec. 31, 2019
Warrant liabilities | Redeemable convertible preferred stock warrants        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Fair value as of beginning of period $ 0 $ 180 $ 181 $ 185
Change in fair value 718 (5)    
Issuance of warrants 0 0    
Exercise of warrants (899) 0    
Fair value as of end of period 0 180    
Warrant liabilities | Private placement warrants        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Fair value as of beginning of period 6,853 0 0 0
Acquired/recognized 7,165      
Change in fair value (312) 0    
Issuance of warrants 0 0    
Exercise of warrants 0 0    
Fair value as of end of period 6,853 0    
Contingent earnout liabilities        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Fair value as of beginning of period 118,749 0 $ 0 $ 0
Acquired/recognized 120,763      
Change in fair value (2,014) 0    
Fair value as of end of period $ 118,749 $ 0