Quarterly report pursuant to Section 13 or 15(d)

Equity - Summary of Unvested Shares (Details)

v3.21.1
Equity - Summary of Unvested Shares (Details) - USD ($)
$ / shares in Units, $ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Restricted Shares of Common Stock      
Shares      
Beginning Balance (in shares) 367,177 750,242 750,242
Granted (in shares) 52,397 194,077  
Vested (in shares) (75,876) (576,880)  
Forfeited (in shares) 0 (262)  
Ending Balance (in shares) 343,698   367,177
Weighted Average Grant Date Fair Value      
Beginning Balance (in usd per share) $ 27.77 $ 20.08 $ 20.08
Granted (in usd per share) 61.58 32.93  
Vested (in usd per share) 20.47 19.50  
Forfeited (in usd per share) 0 $ 28.59  
Ending Balance (in usd per share) $ 34.54   $ 27.77
Value      
Beginning Balance $ 10.2 $ 15.1 $ 15.1
Granted 3.2 6.4  
Vested (1.5) (11.3)  
Forfeited 0.0 $ 0.0  
Ending Balance $ 11.9   $ 10.2
Restricted stock units      
Shares      
Beginning Balance (in shares) 235,600 435,578 435,578
Granted (in shares) 17,426   23,342
Vested (in shares) (342,360)   (439,986)
Forfeited (in shares) 0   (266)
Ending Balance (in shares) 81,846   235,600
Weighted Average Grant Date Fair Value      
Beginning Balance (in usd per share) $ 21.78 $ 20.12 $ 20.12
Granted (in usd per share) 71.23   27.18
Vested (in usd per share) 20.24   19.04
Forfeited (in usd per share) 0   25.90
Ending Balance (in usd per share) $ 35.52   $ 21.78
Value      
Beginning Balance $ 5.1 $ 8.8 $ 8.8
Granted 1.2   0.6
Vested (6.9)   (8.4)
Forfeited 0.0   0.0
Ending Balance $ 2.9   $ 5.1
Restricted stock units | Minimum      
Value      
Vesting percentage 0.00%    
Restricted stock units | Maximum      
Value      
Vesting percentage 200.00%    
Incremental performance shares granted      
Shares      
Granted (in shares) 171,180   216,932
Weighted Average Grant Date Fair Value      
Granted (in usd per share) $ 20.24   $ 18.99
Value      
Granted $ 3.5   $ 4.1
LTIP time-based vesting units      
Shares      
Beginning Balance (in shares) 285,682 201,310 201,310
Granted (in shares) 0 165,346  
Vested (in shares) (60,167) (80,974)  
Forfeited (in shares) 0 0  
Ending Balance (in shares) 225,515   285,682
Weighted Average Grant Date Fair Value      
Beginning Balance (in usd per share) $ 21.62 $ 25.84 $ 25.84
Granted (in usd per share) 0 18.56  
Vested (in usd per share) 25.82 25.87  
Forfeited (in usd per share) 0 $ 0  
Ending Balance (in usd per share) $ 20.50   $ 21.62
Value      
Beginning Balance $ 6.2 $ 5.2 $ 5.2
Granted 0.0 3.1  
Vested (1.6) (2.1)  
Forfeited 0.0 $ 0.0  
Ending Balance $ 4.6   $ 6.2
LTIP market-based vesting units      
Shares      
Beginning Balance (in shares) 312,704 180,500 180,500
Granted (in shares) 0 132,204  
Vested (in shares) 0 0  
Forfeited (in shares) 0 0  
Ending Balance (in shares) 312,704   312,704
Weighted Average Grant Date Fair Value      
Beginning Balance (in usd per share) $ 20.59 $ 26.70 $ 26.70
Granted (in usd per share) 0 12.25  
Vested (in usd per share) 0 0  
Forfeited (in usd per share) 0 $ 0  
Ending Balance (in usd per share) $ 20.59   $ 20.59
Value      
Beginning Balance $ 6.4 $ 4.8 $ 4.8
Granted 0.0 1.6  
Vested 0.0 0.0  
Forfeited 0.0 $ 0.0  
Ending Balance $ 6.4   $ 6.4
LTIP market-based vesting units | Minimum      
Value      
Vesting percentage 0.00%    
LTIP market-based vesting units | Maximum      
Value      
Vesting percentage 200.00%