Derivative and Hedging Financial Instruments - Summary of Realized and Unrealized Gains and Losses Related to Derivative Instrument (Detail) (USD $)	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Gain Loss On Investments [Abstract]
Realized gains (loss) on commodity derivative	$ (260,542)	$ 639
Change in fair value of commodity derivative	(305,650)
Change in fair value of warrant derivative liability		(124,316)
Total realized and unrealized gains recorded	$ (566,192)	$ (123,677)

Realized And Unrealized Gains Losses Related To Derivative Instruments

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- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section 25

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e20148-110875

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- Definition

The difference between the book value and the sale price of agreements to purchase or sell mineral resources, energy, and agricultural products at some future point. This element refers to the gain (loss) included in earnings and not to the cash proceeds.

+ References

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

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