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 6 Months Ended
Jun. 30, 2021
USD ($)
$ / shares
shares
Mar. 31, 2021
$ / shares
shares
Jun. 30, 2021
USD ($)
purchasePeriod
$ / shares
shares
Dec. 31, 2020
USD ($)
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Aggregate intrinsic value of options exercised | $     $ 224,000  
Fair value of options vested | $     $ 35,000  
2018 Stock Option and Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Issuance of common stock shares (in shares)     1,072,356  
Common stock reserved for issuance (in shares) 1,190,332   1,190,332 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 | $ 7,267,000   $ 7,267,000  
Weighed-average period of costs amortized     2 years 6 months  
Unrecognized stock compensation expense | $ $ 47,000   $ 47,000  
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 3,488,262    
Restricted stock units awards grant date fair value (in dollars per share) | $ / shares $ 1.23 $ 2.03 $ 1.23  
Vesting period of award 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    
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%