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Equity-based Awards - Summary of Information Regarding Restricted Common Unit Awards (Detail) - Restricted Common Units [Member] - $ / shares
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Outstanding, Number of Units, Beginning Balance 1,368,538 1,093,520 706,927
Granted, Number of Units 50,000 827,704 684,954
Forfeited, Number of Units (27,537) (69,059) (38,294)
Vested, Number of Units (958,841) (483,627) (260,067)
Outstanding, Number of Units, Ending Balance 432,160 1,368,538 1,093,520
Outstanding, Weighted Average Grant Date Fair Value per unit, Beginning balance $ 17.61 $ 20.93 $ 18.62
Granted, Weighted-Average Grant Date Fair Value per Unit 2.41 14.90 22.39
Forfeited, Weighted-Average Grant Date Fair Value per Unit 16.99 18.35 20.54
Vested, Weighted-Average Grant Date Fair Value per Unit 18.01 20.37 18.56
Outstanding, Weighted Average Grant Date Fair Value per unit, Ending balance $ 15.00 $ 17.61 $ 20.93