Quarterly report pursuant to Section 13 or 15(d)

Share-Based Compensation - Narrative (Details)

v3.21.2
Share-Based Compensation - Narrative (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2021
Mar. 31, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Dec. 31, 2020
RSUs            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Granted (in shares) 66,000   324,000 636,000 556,000  
TSR, maximum percent of performance period 5.00%     5.00%    
Vested (in shares) (184,000)   (90,000) (205,000) (106,000)  
Grant date fair value $ 7.4   $ 0.6 $ 7.8 $ 1.3  
Unrecognized compensation costs $ 29.5     $ 29.5    
Period for recognition (in years)       2 years 3 months 18 days    
Performance-based Equity Awards            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Vested (in shares)       0    
Grant date fair value     $ 0.5   $ 3.4  
Performance-based Equity Awards | Vesting Percentage, Minimum            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award vesting rights   0.00%        
Performance-based Equity Awards | Vesting Percentage, Maximum            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award vesting rights   300.00%        
Cash-Settled RSUs            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Granted (in shares) 3,000   39,000 3,000 125,000  
Vested (in shares) 0   (1,000) (1,000) (2,000)  
Unrecognized compensation costs $ 5.9     $ 5.9    
Period for recognition (in years)       1 year 6 months    
Award vesting period (in years)       3 years    
Cash Stock Appreciation Rights (SARs)            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Unrecognized compensation costs $ 10.2     $ 10.2   $ 1.7