Earnings per Share - Anti-dilutive Securities (Details) - shares
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Restricted Stock Awards      
Earnings per Share      
Antidilutive securities (in shares)     27,430
Restricted Stock Unit Awards      
Earnings per Share      
Antidilutive securities (in shares) 1,249,825 757,245 54,656
Performance Share Unit Awards      
Earnings per Share      
Antidilutive securities (in shares) 1,035,205 539,188 192,998
Class B common stock      
Earnings per Share      
Economic interests/rights (as a percent) 0.00%    
Series A preferred stock      
Earnings per Share      
Antidilutive securities (in shares) 28,880,824