Derivative and Hedging Financial Instruments - Summary of Realized and Unrealized Gains and Losses Related to Derivative Instrument (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Derivative [Line Items]
Total realized and unrealized (losses) gains recorded	$ (2,580,698)	$ (526,920)	$ (1,397,072)	$ 6,848,261
Commodity Contract [Member]
Derivative [Line Items]
Realized gains (loss) on commodity derivatives	1,600,758	10,099,261	2,529,592	12,129,437
Change in fair value of commodity derivatives	$ (4,181,456)	$ (10,626,181)	$ (3,926,664)	$ (5,281,176)