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Incentive Compensation - Summarize Information about Performance Units (Details) - Performance Units - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]      
Unvested, beginning of period (in shares) 1,811,810    
Granted (in shares) 953,638    
Vested (in shares) (1,378,188)    
Forfeited (in shares) (18,178)    
Unvested, end of period (in shares) 1,369,082 1,811,810  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]      
Unvested, beginning of period, weighted average grant date fair value (in usd per share) $ 15.94    
Granted, weighted average grant date fair value (in usd per share) 16.84 $ 17.94 $ 17.99
Vested, weighted average grant date fair value (in usd per share) 14.83    
Forfeited, weighted average grant date fair value (in usd per share) 17.63    
Unvested, end of period, weighted average grant date fair value (in usd per share) $ 17.66 $ 15.94  
Additional shares authorized (in shares) 457,322