Annual report pursuant to Section 13 and 15(d)

STOCK-BASED COMPENSATION - Narrative (Details)

v3.20.4
STOCK-BASED COMPENSATION - Narrative (Details)
$ / shares in Units, $ in Millions
12 Months Ended
Sep. 18, 2020
Dec. 31, 2020
USD ($)
$ / shares
shares
Dec. 31, 2019
USD ($)
$ / shares
shares
Dec. 31, 2018
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Reverse stock split ratio 0.1      
2018 Equity Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Shares available for future awards (in shares) | shares   908,052    
Restricted Stock Awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unrecognized compensation expense | $   $ 3.1    
Unrecognized compensation expense, recognized period   10 months 24 days    
Fair value of vested awards | $   $ 2.7 $ 6.6 $ 3.5
Service, Performance, and Market-based Awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Awards granted (in shares) | shares   0    
Weighted-average grant date fair value of awards granted (in dollars per share)   $ 0    
Weighted average grant date fair value (in dollars per share)   9.80 $ 9.80  
Service, Performance, and Market-based Awards | 2018 Equity Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Weighted average grant date fair value (in dollars per share)   $ 9.80    
Service and Market-based Awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Awards granted (in shares) | shares   0    
Weighted-average grant date fair value of awards granted (in dollars per share)   $ 0    
Weighted average grant date fair value (in dollars per share)   16.70 $ 18.00  
Service and Market-based Awards | 2018 Equity Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Weighted average grant date fair value (in dollars per share)   $ 18.20    
Service-Based RSAs        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Awards granted (in shares) | shares   460,382 174,720 105,035
Weighted-average grant date fair value of awards granted (in dollars per share)   $ 9.15 $ 21.40 $ 26.70
Weighted average grant date fair value (in dollars per share)   10.44 $ 24.10  
2019 Performance Award I        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Weighted average grant date fair value (in dollars per share)   $ 18.80    
Incremental compensation expense | $   $ 2.0    
2019 Performance Award II        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Weighted average grant date fair value (in dollars per share)   $ 10.40    
Incremental compensation expense | $   $ 1.1    
Directors | Restricted Stock Awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period   1 year    
Employees And Officers | Restricted Stock Awards        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period   3 years