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Equity-Based Compensation - Restricted Stock Awards With Market Conditions Additional Information (Details)
$ / shares in Units, $ in Millions
1 Months Ended 12 Months Ended 47 Months Ended
Feb. 28, 2014
trading_day
$ / shares
shares
Dec. 31, 2017
USD ($)
trading_day
shares
Dec. 31, 2016
USD ($)
shares
Dec. 31, 2015
USD ($)
shares
Dec. 31, 2017
shares
Dec. 31, 2014
shares
Dec. 31, 2011
shares
Restricted stock              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Restricted stock vested in period, fair value | $   $ 42.4 $ 6.3 $ 12.8      
Number of shares issued and unvested (in shares)   0 2,644,030 3,480,828 0 3,755,275  
Number of shares forfeited in period (in shares)   167,712 626,319 70,299      
Number of shares, granted (in shares)   340,566 555,680 581,672      
2011 Executive Performance Based Awards              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares issued and unvested (in shares)             366,666
2014 Management Market Based Awards | Restricted stock              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares issued and unvested (in shares) 1,277,500            
Share-based payment award, threshold, number of trading days | trading_day 45            
Number of shares forfeited in period (in shares)         20,000    
2014 Management Market Based Awards | Restricted stock | Tranche one              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Nonvested shares, volume weighted average price per share (in dollars per share) | $ / shares $ 28.07            
Vesting percentage 25.00%            
2014 Management Market Based Awards | Restricted stock | Tranche two              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Nonvested shares, volume weighted average price per share (in dollars per share) | $ / shares $ 30.16            
Vesting percentage 25.00%            
2014 Management Market Based Awards | Restricted stock | Tranche three              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Nonvested shares, volume weighted average price per share (in dollars per share) | $ / shares $ 32.38            
Vesting percentage 25.00%            
2014 Management Market Based Awards | Restricted stock | Tranche four              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Nonvested shares, volume weighted average price per share (in dollars per share) | $ / shares $ 34.71            
Vesting percentage 25.00%            
2014 Employee Market Based Awards | Restricted stock              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Share-based payment award, threshold, number of trading days | trading_day   45          
Number of shares forfeited in period (in shares)   12,600          
Number of shares, granted (in shares)   90,800