Quarterly report pursuant to Section 13 or 15(d)

Equity-Based Compensation and Cash Awards - PSU awards (Details)

v3.21.2
Equity-Based Compensation and Cash Awards - PSU awards (Details)
$ / shares in Units, $ in Millions
1 Months Ended 9 Months Ended
Apr. 30, 2021
item
Jul. 31, 2020
USD ($)
Jan. 31, 2020
USD ($)
tranche
Sep. 30, 2021
USD ($)
$ / shares
shares
Dec. 31, 2020
USD ($)
Cash Awards          
Unvested cash awards recorded in other liabilities | $       $ 2.0 $ 3.2
2013 Plan          
Cash Awards          
Cash awards granted | $     $ 3.3    
Number of tranches related to cash awards | tranche     3    
2020 Plan          
Cash Awards          
Cash awards granted | $   $ 2.6      
Vesting period for cash awards   4 years      
PSUs          
Number of units          
Total awarded and unvested at the beginning of the period (in shares) | shares       2,547,798  
Granted (in shares) | shares       479,120  
Forfeited (in shares) | shares       (67,000)  
Cancelled (unearned) | shares       (1,112,639)  
Total awarded and unvested at the end of the period (in shares) | shares       1,847,279  
Weighted average grant date fair value          
Total awarded and unvested at the beginning of the period (in dollars per share)       $ 12.66  
Granted (in dollars per share)       9.71  
Forfeited (in dollars per share)       2.97  
Cancelled (unearned) (in dollars per share)       19.19  
Total awarded and unvested at the end of the period (in dollars per share)       $ 8.31  
Additional disclosures          
Unamortized equity-based compensation expense | $       $ 8.0  
Weighted average period for recognizing unrecognized stock-based compensation expense       2 years  
Weighted-average assumptions used to calculate fair value of performance share units granted          
Volatility (as a percent)       85.00%  
Risk-free interest rate (as a percent)       0.32%  
Weighted average fair value of awards granted-Absolute TSR       $ 11.99  
PSU Awards Based on TSR          
Stock-based compensation          
Service period 3 years        
PSU Awards Based on TSR | Minimum          
Stock-based compensation          
Number of PSUs that may vest, as a percent 0.00%        
PSU Awards Based on TSR | Maximum          
Stock-based compensation          
Number of PSUs that may vest, as a percent 200.00%        
PSU Awards Based on TSR | One Year Period          
Stock-based compensation          
Number of performance periods | item 3        
Service period 1 year        
PSU Awards Based on TSR | Three Year Period          
Stock-based compensation          
Number of cumulative performance periods | item 1        
Service period 3 years        
PSU Awards Based On Leverage Ratio          
Stock-based compensation          
Number of performance periods | item 3        
Service period 1 year        
PSU Awards Based On Leverage Ratio | Minimum          
Stock-based compensation          
Number of PSUs that may vest, as a percent 0.00%        
PSU Awards Based On Leverage Ratio | Maximum          
Stock-based compensation          
Number of PSUs that may vest, as a percent 200.00%