Supplemental Disclosures about Oil and Natural Gas Producing Properties (unaudited) - Standardized Measure of Discounted Future Net Cash Flows Related to Proved Oil and Natural Gas Reserves (Details) (USD $)	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2011
Standardized measure of discounted future net cash flows
Future cash inflows	$ 1,193,515,075	$ 1,436,980,607	$ 1,355,686,188
Future production costs and severance taxes	(475,387,931)	(510,902,614)	(458,716,938)
Future development costs	(46,154,178)	(60,742,406)	(38,458,724)
Future income tax expenses	(195,581,510)	(275,113,560)	(296,703,838)
Future net cash flows	476,391,456	590,222,027	561,806,688
10% annual discount for estimated timing of cash flows	(250,313,784)	(283,001,328)	(278,209,195)
Standardized measure of discounted future net cash flows	$ 226,077,672	$ 307,220,699	$ 283,597,493	$ 228,447,954

Supplemental Disclosures about Oil and Natural Gas Producing Properties (unaudited) - Standardized Measure of Discounted Future Net Cash Flows Related to Proved Oil and Natural Gas Reserves (Details) (USD $)

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2012

Jun. 30, 2011

Standardized measure of discounted future net cash flows

Future cash inflows

$ 1,193,515,075

$ 1,436,980,607

$ 1,355,686,188

Future production costs and severance taxes

(475,387,931)

(510,902,614)

(458,716,938)

Future development costs

(46,154,178)

(60,742,406)

(38,458,724)

Future income tax expenses

(195,581,510)

(275,113,560)

(296,703,838)

Future net cash flows

476,391,456

590,222,027

561,806,688

10% annual discount for estimated timing of cash flows

(250,313,784)

(283,001,328)

(278,209,195)

Standardized measure of discounted future net cash flows

$ 226,077,672

$ 307,220,699

$ 283,597,493

$ 228,447,954

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Amount of estimated future accumulated cash inflow from the sale of proved oil and gas reserves.

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Amount of estimated future accumulated cash outflow for costs to be incurred in developing proved oil and gas reserves.

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Amount of estimated future accumulated cash outflow for income tax, based on the future income less future expense derived from production and sale of proved oil and gas reserves.

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Amount, after future accumulated cash outflow for development and production costs and future income tax, of estimated future accumulated cash inflow from the sale of proved oil and gas reserves.

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Amount of estimated future accumulated cash outflow for costs to be incurred in producing proved oil and gas reserves.

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Amount of discount on future accumulated cash inflow, after deducting future accumulated cash outflow for development and production costs and future income tax, from sale of proved oil and gas reserves, using a discount rate of ten percent a year.

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Amount of discounted future accumulated cash inflow relating to proved oil and gas reserves.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

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