Derivative and Hedging Financial Instruments - Summary of Fair Value of Derivatives (Detail) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Derivative [Line Items]
Commodity derivative, Current assets	$ 1,091,835	$ 3,417,887
Commodity derivative, Noncurrent assets	1,104,800	2,423,508
Derivative assets fair value	2,196,635	5,841,395
Commodity derivative, Current liabilities	28,234	474,696
Commodity derivative, Noncurrent liabilities	344,246	1,253,024
Derivative liabilities fair value	372,480	1,727,720
Commodity Contract [Member]
Derivative [Line Items]
Commodity derivative, Current assets	1,091,835	3,417,887
Commodity derivative, Noncurrent assets	1,104,800	2,423,508
Derivative assets fair value	2,196,635	5,841,395
Commodity derivative, Current liabilities	28,234	474,696
Commodity derivative, Noncurrent liabilities	344,246	1,253,024
Derivative liabilities fair value	$ 372,480	$ 1,727,720

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