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Equity-based Awards - Additional Information (Detail) - USD ($)
$ in Millions
1 Months Ended 12 Months Ended
Jun. 01, 2016
Mar. 09, 2016
Jun. 30, 2016
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Reversed share based compensation $ 0.1 $ 0.5        
Fair value of compensation cost recognized on the date of plan modification $ 0.5 $ 0.3        
Restricted Common Units [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Unrecognized compensation cost       $ 3.8    
Weighted-average period of unrecognized compensation cost       1 year 1 month 6 days    
Cash distributions paid       $ 0.2 $ 2.8 $ 1.9
Certain Employee [Member] | Phantom Units [Member] | First Anniversary Of Grant Date [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Vesting percentage from the date of grant     33.33%      
Certain Employee [Member] | Phantom Units [Member] | Second Anniversary Of Grant Date [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Vesting percentage from the date of grant     33.33%      
Certain Employee [Member] | Phantom Units [Member] | Third Anniversary Of Grant Date [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Vesting percentage from the date of grant     33.33%      
Long-Term Incentive Plan [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Number of common units for awards authorized       2,142,221    
Long-Term Incentive Plan [Member] | Executive officers and employees [Member] | Restricted Common Units [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Fair value of the restricted common units       $ 0.1 $ 12.3 $ 15.0