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Incentive Compensation - Additional Information (Details) - USD ($)
3 Months Ended 12 Months Ended
Jun. 30, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Cash Bonus, requisite service period   4 years    
Cash reclassified to equity settled liabilities $ 10,100,000      
Granted, weighted average grant date fair value (in usd per share)   $ 18.48 $ 10.09 $ 18.79
Fair value of units vested   $ 11,900,000 $ 9,400,000 $ 25,100,000
Cash payments of vested units   $ 0 $ 0 $ 0
Restricted Common Units        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Grant of stock units   901,910    
Granted, weighted average grant date fair value (in usd per share)   $ 18.48    
Unrecognized compensation cost   $ 15.7    
Period of weighted average recognition   1 year 7 months 24 days    
Subordinated Units        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Grant of stock units   0    
Granted, weighted average grant date fair value (in usd per share)   $ 0.00    
Unrecognized compensation cost   $ 0.2    
Period of weighted average recognition   2 months 12 days    
Performance Units        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Grant of stock units   438,288    
Granted, weighted average grant date fair value (in usd per share)   $ 17.99    
Unrecognized compensation cost   $ 10,100,000    
Period of weighted average recognition   1 year 6 months 15 days