Changes in Standardized Measure of Discounted Future Net Cash Flows (Detail) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Standardized measure of discounted future net cash flows, beginning of year	$ 8,342,000
Sales of oil and gas, net of production costs and taxes	(1,243,343)	(440,596)
Changes in estimated future development costs	129,194	(918,376)
Purchases of reserves in place		15,846,975
Sales of reserves in place	(238,347)	(3,622,558)
Revisions of previous estimates	(1,013,042)
Changes in prices and production costs	(729,103)
Net changes in future income taxes	951,631	(2,523,445)
Accretion of discount	834,200
Standardized measure of discounted future net cash flows, end of year	$ 7,033,190	$ 8,342,000

The increase in the net discounted value of the proved oil and gas reserves due only to the passage of time.

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The change in the discounted value of the proved oil and gas reserves due to financial transactions where reserves (minerals in place) were sold.

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The increase (decrease) in the evaluation or calculation of the costs that will be required in future periods to make it possible to extract or process proved oil and gas reserves.

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The increase (decrease) in the estimate of future income taxes that will be due on future pretax net cash flows relating to the enterprise's proved oil and gas reserves.

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The change in the discounted value of the proved oil and gas reserves due to financial transactions where new reserves were purchased.

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The increase (decrease) in sales and transfer prices and in production (lifting) costs related to future production. The effects of changes in prices and costs are computed before the effects of changes in quantities.

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Any changes made during the period to the evaluation or calculation of the estimated quantity of oil or gas in proved reserves.

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The amount of sales or transfers of oil gas that was previously included in proved oil and gas reserves. This amount is net of production costs.

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The balance as of the balance sheet date of the standardized measure of discounted future net cash flow relating to proved oil and gas reserves.

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