Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation (RSU Equity Awards (Details)

v3.19.3.a.u2
Share-Based Compensation (RSU Equity Awards (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
RSU equity awards      
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]      
Unvested at the beginning of the period (in shares) 2,103,000 1,790,000 1,448,000
Granted (in shares) 1,881,000 872,000 1,173,000
Vested (in shares) (1,062,000) (506,000) (797,000)
Forfeited (in shares) (227,000) (53,000) (34,000)
Unvested at the end of the period (in shares) 2,695,000 2,103,000 1,790,000
Weighted Average Grant-Date Fair Value per Share      
Unvested at the beginning of the period, Grant Date Fair Value per Share (usd per share) $ 13.24 $ 11.54 $ 10.81
Granted, grant date fair value per share (usd per share) 8.60 13.89 12.25
Vested, grant date fair value per share (usd per share) 12.35 9.56 11.35
Forfeited, grant date fair value per share (usd per share) 10.59 11.43 9.57
Unvested at the end of the period, grant date fair value per share (usd per share) $ 10.57 $ 13.24 $ 11.54
Share-based compensation arrangement vesting rights, percentage     142.00%
Fair value of shares vested $ 7.3 $ 6.3 $ 9.0
RSU equity awards | Vesting range 0 to 200%      
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]      
Unvested at the beginning of the period (in shares) 208,000 89,000  
Unvested at the end of the period (in shares) 399,425 208,000 89,000
RSU equity awards | Vesting Minimum      
Weighted Average Grant-Date Fair Value per Share      
Share-based compensation arrangement vesting rights, percentage 0.00%    
RSU equity awards | Vesting Maximum      
Weighted Average Grant-Date Fair Value per Share      
Share-based compensation arrangement vesting rights, percentage 200.00%    
Performance-based RSU      
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]      
Unvested at the beginning of the period (in shares)   73,000  
Unvested at the end of the period (in shares)     73,000
Weighted Average Grant-Date Fair Value per Share      
Fair value of shares vested $ 4.3 $ 3.5 $ 2.6