2.4.0.84173 - Disclosure - Supplemental Disclosures about Oil and Natural Gas Producing Properties (unaudited) (Details 4)truefalsefalse1false USDfalsefalse$D2013http://www.sec.gov/CIK0001006655duration2012-07-01T00:00:002013-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$D2012http://www.sec.gov/CIK0001006655duration2011-07-01T00:00:002012-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$D2011http://www.sec.gov/CIK0001006655duration2010-07-01T00:00:002011-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 2us-gaap_IncreaseDecreaseInStandardizedMeasureOfDiscountedFutureNetCashFlowRelatingToProvedOilAndGasReservesRollForwardus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Changes in the standardized measure of discounted future net cash flows applicable to proved crude oil, natural gas liquids, and natural gas reserves2false 3us-gaap_StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesus-gaap_truedebitinstantfalsefalsefalsefalsefalsetruefalsefalseperiodStartLabel1truefalsefalse283597493283597493USD$falsetruefalse2truefalsefalse228447954228447954USD$falsetruefalse3truefalsefalse161626649161626649USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe balance as of the balance sheet date of the standardized measure of discounted future net cash flow relating to proved oil and gas reserves.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62500-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=8451751&loc=d3e63123-109448 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59BB -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Net changes in sales prices and production costs related to future production4false 3us-gaap_IncreaseDecreaseInEstimatedFutureDevelopmentCostsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-566125-566125falsefalsefalse2truefalsefalse63401236340123falsefalsefalse3truefalsefalse-16028728-16028728falsefalsefalsexbrli:monetaryItemTypemonetaryThe 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.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62455-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Changes in estimated future development costs5false 3us-gaap_SalesAndTransfersOfOilAndGasProducedNetOfProductionCostsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-19569182-19569182falsefalsefalse2truefalsefalse-16187039-16187039falsefalsefalse3truefalsefalse-6151549-6151549falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of sales or transfers of oil gas that was previously included in proved oil and gas reserves. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Sales of oil and gas produced during the period, net of production costs6false 3us-gaap_ExtensionsDiscoveriesAdditionsAndImprovedRecoveryLessRelatedCostsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse16061221606122falsefalsefalse3truefalsefalse623446623446falsefalsefalsexbrli:monetaryItemTypemonetaryThis is the amount that proved oil and gas reserves increased due to extensions (increased estimates in the size of proven reserves), discoveries, additions, and improved recovery (increase in ability to extract oil and gas from existing reserves).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62500-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59BB -Subparagraph d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Net change due to extensions, discoveries, and improved recovery7false 3us-gaap_RevisionsOfPreviousQuantityEstimatesus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse6481754464817544falsefalsefalse2truefalsefalse-11975496-11975496falsefalsefalse3truefalsefalse5676622056766220falsefalsefalsexbrli:monetaryItemTypemonetaryAny changes made during the period to the evaluation or calculation of the estimated quantity of oil or gas in proved reserves.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62500-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59BB -Subparagraph f -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Accretion of discount11false 3us-gaap_IncreaseDecreaseInFutureIncomeTaxExpenseEstimatesOnFutureCashFlowsRelatedToProvedOilAndGasReservesus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1017595710175957falsefalsefalse2truefalsefalse-15026628-15026628falsefalsefalse3truefalsefalse-42490270-42490270falsefalsefalsexbrli:monetaryItemTypemonetaryThe 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.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 19 -Paragraph 59Y -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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