XML 89 R78.htm IDEA: XBRL DOCUMENT v3.21.2
Stockholders' Equity - Stock-based Compensation - Additional Information (Details)
9 Months Ended
Sep. 30, 2021
Employee Stock Option  
Class Of Stock [Line Items]  
Stock option term 10 years
Employee Stock Option | 2008 Plan | Tranche One  
Class Of Stock [Line Items]  
Stock granted to employees vesting rights, percentage 25.00%
Employee Stock Option | 2008 Plan | Tranche Two  
Class Of Stock [Line Items]  
Stock granted to employees vesting rights, terms of award one year and then 1/48th monthly thereafter
Employee Stock Option | 2017 Plan  
Class Of Stock [Line Items]  
Stock option term 10 years
Employee Stock Option | 2017 Plan | Minimum [Member]  
Class Of Stock [Line Items]  
Share-based compensation arrangement by share-based payment vesting period 1 year
Employee Stock Option | 2017 Plan | Maximum  
Class Of Stock [Line Items]  
Share-based compensation arrangement by share-based payment vesting period 4 years
Restricted Stock Units  
Class Of Stock [Line Items]  
Share-based compensation arrangement by share-based payment vesting period 4 years