XML 71 R53.htm IDEA: XBRL DOCUMENT v3.22.1
Stock-Based Compensation - Additional Information (Details)
$ / shares in Units, $ in Thousands
1 Months Ended 12 Months Ended
Jan. 01, 2022
shares
Mar. 31, 2020
purchasePeriod
Oct. 31, 2018
shares
Dec. 31, 2021
USD ($)
$ / shares
shares
Dec. 31, 2020
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Weighted average fair value of options granted (in usd per share) | $ / shares       $ 2.46 $ 3.20
Intrinsic value of share option awards exercised | $       $ 300 $ 100
Stock-based compensation | $       $ 2,268 2,237
Employee stock purchase plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares authorized (in shares)     196,000 490,000  
Additional common stock reserved for future issuance (in shares)       822,051  
Percentage of outstanding stock maximum     1.00%    
Unrecognized compensation expense | $       $ 100  
Weighted-average period expected to be recognized       6 months  
Percentage of employee's maximum compensation   15.00%      
Offering period   24 months      
Number of purchase periods | purchasePeriod   4      
Purchase period term   6 months      
Purchase price of common stock, percent   85.00%      
Stock-based compensation | $       $ 300 $ 100
Common stock purchased (in shares)       138,952 62,063
Weighted average purchase price (in usd per share) | $ / shares       $ 2.42 $ 3.00
Employee stock purchase plan | Subsequent Event          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Additional shares available for grant to ESPP (in shares) 481,906        
Employee Stock Option          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Unrecognized compensation expense | $       $ 4,000  
Weighted-average period expected to be recognized       2 years 6 months  
2018 Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares authorized (in shares)     3,231,626    
Additional common stock reserved for future issuance (in shares)       817,722  
2018 Plan | Subsequent Event          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of options or stock awards available for grant under the plan (in shares) 1,927,624        
2018 Plan | Minimum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Percentage of outstanding stock maximum     3.00%    
2018 Plan | Maximum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Percentage of outstanding stock maximum     4.00%