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Supplemental Disclosures about Oil and Natural Gas Producing Properties (unaudited) - Estimated Quantities of Proved Oil and Natural Gas Reserves (Details) | 12 Months Ended |
--- | --- | ---
Jun. 30, 2014 Boe | Jun. 30, 2013 Boe | Jun. 30, 2012 Boe | Jun. 30, 2011 Boe
Estimated quantities of proved oil and natural gas reserves and changes in quantities of proved developed and undeveloped reserves |  |  |  |  |  |
Balance at the beginning of the period (in BOE) | 13,766,440 |  | 13,441,116 |  | 13,847,462 |
Revisions of previous estimates (in BOE) | (247,350) | [1] | 2,806,181 | [2] | (344,440) |
Improved recovery, extensions and discoveries (in BOE) | 132,884 |  |  |  | 146,249 |
Sales of minerals in place (in BOE) | (184,722) |  | (2,254,038) |  |  |
Production (sales volumes) (in BOE) | (177,742) |  | (226,819) |  | (208,155) |
Balance at the end of the period (in BOE) | 13,289,510 |  | 13,766,440 |  | 13,441,116 |
Proved developed reserves (in BOE) | 7,970,562 |  | 10,089,861 |  | 8,032,809 | 5,344,471
Crude Oil |  |  |  |  |  |
Estimated quantities of proved oil and natural gas reserves and changes in quantities of proved developed and undeveloped reserves |  |  |  |  |  |
Balance at the beginning of the period (in Bbls/Mcf) | 12,782,755 |  | 11,638,618 |  | 11,567,846 |
Revisions of previous estimates (in Bbls/Mcf) | (1,919,052) | [1] | 1,826,053 | [2] | 84,219 |
Improved recovery, extensions and discoveries (in Bbls/Mcf) | 17,146 |  |  |  | 137,634 |
Sales of minerals in place (in Bbls/Mcf) | (184,722) |  | (485,536) |  |  |
Production (sales volumes) (in Bbls/Mcf) | (169,783) |  | (196,380) |  | (151,081) |
Balance at the end of the period (in Bbls/Mcf) | 10,526,344 |  | 12,782,755 |  | 11,638,618 |
Estimated quantities of proved oil and natural gas reserves and changes in quantities of proved developed and undeveloped reserves |  |  |  |  |  |
Proved developed reserves (in Bbls/Mcf) | 7,858,224 |  | 10,077,522 |  | 7,670,934 | 4,986,337
Natural Gas Liquids |  |  |  |  |  |
Estimated quantities of proved oil and natural gas reserves and changes in quantities of proved developed and undeveloped reserves |  |  |  |  |  |
Balance at the beginning of the period (in Bbls/Mcf) | 979,885 |  | 492,473 |  | 712,300 |
Revisions of previous estimates (in Bbls/Mcf) | 1,269,588 | [1] | 975,515 | [2] | (212,677) |
Improved recovery, extensions and discoveries (in Bbls/Mcf) | 32,731 |  |  |  | 5,461 |
Sales of minerals in place (in Bbls/Mcf) | 0 |  | (480,832) |  |  |
Production (sales volumes) (in Bbls/Mcf) | (3,516) |  | (7,271) |  | (12,611) |
Balance at the end of the period (in Bbls/Mcf) | 2,278,688 |  | 979,885 |  | 492,473 |
Estimated quantities of proved oil and natural gas reserves and changes in quantities of proved developed and undeveloped reserves |  |  |  |  |  |
Proved developed reserves (in Bbls/Mcf) | 32,164 |  | 8,539 |  | 111,978 | 100,900
Natural Gas |  |  |  |  |  |
Estimated quantities of proved oil and natural gas reserves and changes in quantities of proved developed and undeveloped reserves |  |  |  |  |  |
Balance at the beginning of the period (in Bbls/Mcf) | 22,797 |  | 7,860,156 |  | 9,403,899 |
Revisions of previous estimates (in Bbls/Mcf) | 2,412,677 | [1] | 27,679 | [2] | (1,295,893) |
Improved recovery, extensions and discoveries (in Bbls/Mcf) | 498,044 |  |  |  | 18,925 |
Sales of minerals in place (in Bbls/Mcf) | 0 |  | (7,726,032) |  |  |
Production (sales volumes) (in Bbls/Mcf) | (26,655) |  | (139,006) |  | (266,775) |
Balance at the end of the period (in Bbls/Mcf) | 2,906,863 |  | 22,797 |  | 7,860,156 |
Estimated quantities of proved oil and natural gas reserves and changes in quantities of proved developed and undeveloped reserves |  |  |  |  |  |
Proved developed reserves (in Bbls/Mcf) | 481,042 |  | 22,797 |  | 1,499,382 | 1,543,401
[1] | Significant reserve revisions occurred in the Delhi Field during fiscal 2014. As a result of an adverse fluid release event in the Field, certain oil reserves were reclassified from proved to an unproved category based on the operator's decision to defer CO2 injections in certain parts of the Field. There was a positive revision to estimated proved reserves of natural gas liquids and natural gas as a result of an improved design for the gas plant in the Delhi Field. The plant is expected to significantly increase recoveries of these products, particularly natural gas, which was not previously planned to be extracted from the injection volumes.
[2] | A significant upward reserve revision occurred in the Delhi Field during fiscal 2013 as a result of (1) revised geological maps based on production results and acquired seismic data, (2) inclusion of an additional reservoir with similar features, production history and suitability for EOR, and (3) inclusion of natural gas processing at Delhi.

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- Definition Additions to proved reserves, measured in energy equivalents, that result from (1) improved recovery (2) extension of the proved acreage of previously discovered (old) reservoirs through additional drilling in periods after discovery and (3) discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields. + References No definition available. + Details
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- Definition The net quantity of proved reserves as of the balance sheet date. Proved oil reserves are the estimated quantities of crude oil and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61831-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10.(a)(2)) -URI http://asc.fasb.org/extlink&oid=27015464&loc=d3e511914-122862 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 10 -Paragraph a -Subparagraph 2 -Article 4 + Details
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- Definition Net quantities of an enterprise's interests in proved developed reserves of either crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other nonrenewable natural resource that is intended to be upgraded into synthetic oil and gas as of the beginning and the end of the year. "Net" quantities of reserves include those relating to the enterprise's operating and nonoperating interests in properties. Quantities of reserves relating to royalty interests owned are included in "net" quantities if the necessary information is available to the enterprise. "Net" quantities does not include reserves relating to interests of others in properties owned by the enterprise. The unit of measure for reserve quantities is defined as "barrels" for oil and synthetic oil reserves or "cubic feet" or "cubic meters" for natural gas and synthetic gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61797-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61884-109447 + Details
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