Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Narrative (Details)

v3.21.2
Stock-Based Compensation - Narrative (Details)
 3 Months Ended 9 Months Ended
Sep. 30, 2021
USD ($)
office
$ / shares
shares
Jun. 30, 2021
$ / shares
shares
Mar. 31, 2021
$ / shares
shares
Sep. 30, 2021
USD ($)
purchasePeriod
$ / shares
shares
Dec. 31, 2020
USD ($)
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Stock options granted (in shares) 50,000     0  
Exercise price of stock options granted (in dollars per share) | $ / shares $ 1.08     $ 0  
Aggregate intrinsic value of options exercised | $       $ 295,000  
Fair value of options vested | $       $ 50,000  
2018 Stock Option and Incentive Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Issuance of common stock shares (in shares)       1,068,271  
Common stock reserved for issuance (in shares) 1,227,964     1,227,964 2,551,720
2018 Employee Stock Purchase Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common stock reserved for issuance (in shares) 272,942     272,942 272,942
Maximum payroll deductions (as a percent) 15.00%     15.00%  
Maximum yearly contribution | $ $ 25,000,000     $ 25,000,000  
Maximum number of shares participant may purchase       4,000  
Offering period       24 months  
Number of purchase periods | purchasePeriod       4  
Purchase period for award       6 months  
ESPP, purchase price percentage       85.00%  
2009 Stock Option and Incentive Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Unvested shares (in shares) 574     574 574
Accrued expenses | $ $ 1,000     $ 1,000 $ 1,000
Unamortized fair value of restricted stock units | $ 5,881,000     $ 5,881,000  
Weighed-average period of costs amortized       2 years 8 months 12 days  
Unrecognized stock compensation expense | $ $ 33,000     $ 33,000  
Employee Stock | 2018 Employee Stock Purchase Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Annual percentage increase 3.00%     3.00%  
Percent of shares outstanding on last day 1.50%     1.50%  
Restricted Stock Units (RSUs) - Team Members          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Restricted stock unit awards granted (in shares) 54,000 54,000 3,488,262    
Restricted stock units awards grant date fair value (in dollars per share) | $ / shares $ 1.09 $ 1.23 $ 2.03 $ 1.09  
Vesting period of award 47 months 47 months      
Restricted Stock Units (RSUs) - Team Members | Minimum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vesting period of award     10 months    
Restricted Stock Units (RSUs) - Team Members | Maximum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vesting period of award     51 months    
Restricted Stock Units (RSUs) - Non-Employee Directors | Share-based Payment Arrangement, Tranche One          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Restricted stock unit awards granted (in shares)     652,170    
Restricted stock units awards grant date fair value (in dollars per share) | $ / shares     $ 1.22    
Restricted Stock Units (RSUs) - Non-Employee Directors | Share-based Payment Arrangement, Tranche Two          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Restricted stock unit awards granted (in shares)     97,744    
Restricted stock units awards grant date fair value (in dollars per share) | $ / shares     $ 1.22    
Options          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vesting period of award 1 year        
Number of equal monthly installments | office 12        
Post-Closing Outstanding Shares | Employee Stock | 2018 Stock Option and Incentive Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Annual percentage increase 10.00%     10.00%  
Outstanding Shares on Last Day of Immediately Preceding Year | Employee Stock | 2018 Stock Option and Incentive Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Annual percentage increase 5.00%     5.00%