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Condensed Consolidating Financial Statements - Schedule of Consolidating Statement of Operations (Detail) (USD $) | 3 Months Ended | 12 Months Ended
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Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Revenues |  |  |  |  |  |  |  |  |  |  |
Oil and gas revenues |  |  |  |  |  |  |  |  | $ 1,304,004,000 us-gaap_OilAndGasSalesRevenue | $ 1,084,412,000 us-gaap_OilAndGasSalesRevenue | $ 670,491,000 us-gaap_OilAndGasSalesRevenue
Well services and midstream revenues |  |  |  |  |  |  |  |  | 86,224,000 us-gaap_RevenueOilAndGasServices | 57,587,000 us-gaap_RevenueOilAndGasServices | 16,177,000 us-gaap_RevenueOilAndGasServices
Total revenues | 299,672,000 us-gaap_OilAndGasRevenue | 368,659,000 us-gaap_OilAndGasRevenue | 372,378,000 us-gaap_OilAndGasRevenue | 349,519,000 us-gaap_OilAndGasRevenue | 333,615,000 us-gaap_OilAndGasRevenue | 305,498,000 us-gaap_OilAndGasRevenue | 254,582,000 us-gaap_OilAndGasRevenue | 248,304,000 us-gaap_OilAndGasRevenue | 1,390,228,000 us-gaap_OilAndGasRevenue | 1,141,999,000 us-gaap_OilAndGasRevenue | 686,668,000 us-gaap_OilAndGasRevenue
Expenses |  |  |  |  |  |  |  |  |  |  |
Lease operating expenses |  |  |  |  |  |  |  |  | 169,600,000 us-gaap_LeaseOperatingExpense | 94,634,000 us-gaap_LeaseOperatingExpense | 54,924,000 us-gaap_LeaseOperatingExpense
Well services and midstream operating expenses |  |  |  |  |  |  |  |  | 50,252,000 us-gaap_WellServiceExpense | 30,713,000 us-gaap_WellServiceExpense | 11,774,000 us-gaap_WellServiceExpense
Marketing, transportation and gathering expenses |  |  |  |  |  |  |  |  | 29,133,000 us-gaap_GasGatheringTransportationMarketingAndProcessingCosts | 25,924,000 us-gaap_GasGatheringTransportationMarketingAndProcessingCosts | 9,257,000 us-gaap_GasGatheringTransportationMarketingAndProcessingCosts
Production taxes |  |  |  |  |  |  |  |  | 127,648,000 us-gaap_ProductionTaxExpense | 100,537,000 us-gaap_ProductionTaxExpense | 62,965,000 us-gaap_ProductionTaxExpense
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  | 412,334,000 us-gaap_DepreciationDepletionAndAmortization | 307,055,000 us-gaap_DepreciationDepletionAndAmortization | 206,734,000 us-gaap_DepreciationDepletionAndAmortization
Exploration expenses |  |  |  |  |  |  |  |  | 3,064,000 us-gaap_ExplorationExpense | 2,260,000 us-gaap_ExplorationExpense | 3,250,000 us-gaap_ExplorationExpense
Impairment of oil and gas properties |  |  |  |  |  |  |  |  | 47,238,000 us-gaap_ImpairmentOfOilAndGasProperties | 1,168,000 us-gaap_ImpairmentOfOilAndGasProperties | 3,581,000 us-gaap_ImpairmentOfOilAndGasProperties
General and administrative expenses |  |  |  |  |  |  |  |  | 92,306,000 us-gaap_GeneralAndAdministrativeExpense | 75,310,000 us-gaap_GeneralAndAdministrativeExpense | 57,190,000 us-gaap_GeneralAndAdministrativeExpense
Total expenses |  |  |  |  |  |  |  |  | 931,575,000 us-gaap_CostsAndExpenses | 637,601,000 us-gaap_CostsAndExpenses | 409,675,000 us-gaap_CostsAndExpenses
Gain on sale of properties |  |  |  |  |  |  |  |  | 186,999,000 us-gaap_GainLossOnSaleOfProperty | 0 us-gaap_GainLossOnSaleOfProperty | 0 us-gaap_GainLossOnSaleOfProperty
Operating income | 15,924,000 us-gaap_OperatingIncomeLoss | 134,103,000 us-gaap_OperatingIncomeLoss | 166,545,000 us-gaap_OperatingIncomeLoss | 329,080,000 us-gaap_OperatingIncomeLoss | 122,133,000 us-gaap_OperatingIncomeLoss | 150,862,000 us-gaap_OperatingIncomeLoss | 113,450,000 us-gaap_OperatingIncomeLoss | 117,953,000 us-gaap_OperatingIncomeLoss | 645,652,000 us-gaap_OperatingIncomeLoss | 504,398,000 us-gaap_OperatingIncomeLoss | 276,993,000 us-gaap_OperatingIncomeLoss
Other income (expense) |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on derivative instruments |  |  |  |  |  |  |  |  | 327,011,000 us-gaap_DerivativeGainLossOnDerivativeNet | (35,432,000)us-gaap_DerivativeGainLossOnDerivativeNet | 34,164,000 us-gaap_DerivativeGainLossOnDerivativeNet
Interest expense, net of capitalized interest |  |  |  |  |  |  |  |  | (158,390,000)us-gaap_InterestExpense | (107,165,000)us-gaap_InterestExpense | (70,143,000)us-gaap_InterestExpense
Other income (expense) |  |  |  |  |  |  |  |  | 195,000 us-gaap_OtherNonoperatingIncomeExpense | 1,216,000 us-gaap_OtherNonoperatingIncomeExpense | 4,860,000 us-gaap_OtherNonoperatingIncomeExpense
Total other income (expense) |  |  |  |  |  |  |  |  | 168,816,000 us-gaap_NonoperatingIncomeExpense | (141,381,000)us-gaap_NonoperatingIncomeExpense | (31,119,000)us-gaap_NonoperatingIncomeExpense
Income before income taxes |  |  |  |  |  |  |  |  | 814,468,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments | 363,017,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments | 245,874,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Income tax benefit (expense) |  |  |  |  |  |  |  |  | (307,591,000)us-gaap_IncomeTaxExpenseBenefit | (135,058,000)us-gaap_IncomeTaxExpenseBenefit | (92,486,000)us-gaap_IncomeTaxExpenseBenefit
Net income | 176,504,000 us-gaap_NetIncomeLoss | 121,587,000 us-gaap_NetIncomeLoss | 38,833,000 us-gaap_NetIncomeLoss | 169,953,000 us-gaap_NetIncomeLoss | 54,490,000 us-gaap_NetIncomeLoss | 54,499,000 us-gaap_NetIncomeLoss | 67,119,000 us-gaap_NetIncomeLoss | 51,851,000 us-gaap_NetIncomeLoss | 506,877,000 us-gaap_NetIncomeLoss | 227,959,000 us-gaap_NetIncomeLoss | 153,388,000 us-gaap_NetIncomeLoss
Parent/Issuer [Member] |  |  |  |  |  |  |  |  |  |  |
Expenses |  |  |  |  |  |  |  |  |  |  |
General and administrative expenses |  |  |  |  |  |  |  |  | 23,528,000 us-gaap_GeneralAndAdministrativeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 14,044,000 us-gaap_GeneralAndAdministrativeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 12,591,000 us-gaap_GeneralAndAdministrativeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Total expenses |  |  |  |  |  |  |  |  | 23,528,000 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 14,044,000 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 12,591,000 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Operating income |  |  |  |  |  |  |  |  | (23,528,000)us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | (14,044,000)us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | (12,591,000)us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Other income (expense) |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  |  |  |  |  |  |  | 613,601,000 oas_EquityInEarningsInSubsidiaries / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 299,459,000 oas_EquityInEarningsInSubsidiaries / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 202,924,000 oas_EquityInEarningsInSubsidiaries / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Interest expense, net of capitalized interest |  |  |  |  |  |  |  |  | (147,230,000)us-gaap_InterestExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | (99,663,000)us-gaap_InterestExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | (67,651,000)us-gaap_InterestExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Other income (expense) |  |  |  |  |  |  |  |  | 5,000 us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | (335,000)us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 1,118,000 us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Total other income (expense) |  |  |  |  |  |  |  |  | 466,376,000 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 199,461,000 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 136,391,000 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Income before income taxes |  |  |  |  |  |  |  |  | 442,848,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 185,417,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 123,800,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Income tax benefit (expense) |  |  |  |  |  |  |  |  | 64,029,000 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 42,542,000 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 29,588,000 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Net income |  |  |  |  |  |  |  |  | 506,877,000 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 227,959,000 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_ParentCompanyMember | 153,388,000 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_ParentCompanyMember
Combined Guarantor Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  |  |
Oil and gas revenues |  |  |  |  |  |  |  |  | 1,304,004,000 us-gaap_OilAndGasSalesRevenue / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 1,084,412,000 us-gaap_OilAndGasSalesRevenue / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 670,491,000 us-gaap_OilAndGasSalesRevenue / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Well services and midstream revenues |  |  |  |  |  |  |  |  | 86,224,000 us-gaap_RevenueOilAndGasServices / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 57,587,000 us-gaap_RevenueOilAndGasServices / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 16,177,000 us-gaap_RevenueOilAndGasServices / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Total revenues |  |  |  |  |  |  |  |  | 1,390,228,000 us-gaap_OilAndGasRevenue / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 1,141,999,000 us-gaap_OilAndGasRevenue / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 686,668,000 us-gaap_OilAndGasRevenue / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Expenses |  |  |  |  |  |  |  |  |  |  |
Lease operating expenses |  |  |  |  |  |  |  |  | 169,600,000 us-gaap_LeaseOperatingExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 94,634,000 us-gaap_LeaseOperatingExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 54,924,000 us-gaap_LeaseOperatingExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Well services and midstream operating expenses |  |  |  |  |  |  |  |  | 50,252,000 us-gaap_WellServiceExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 30,713,000 us-gaap_WellServiceExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 11,774,000 us-gaap_WellServiceExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Marketing, transportation and gathering expenses |  |  |  |  |  |  |  |  | 29,133,000 us-gaap_GasGatheringTransportationMarketingAndProcessingCosts / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 25,924,000 us-gaap_GasGatheringTransportationMarketingAndProcessingCosts / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 9,257,000 us-gaap_GasGatheringTransportationMarketingAndProcessingCosts / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Production taxes |  |  |  |  |  |  |  |  | 127,648,000 us-gaap_ProductionTaxExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 100,537,000 us-gaap_ProductionTaxExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 62,965,000 us-gaap_ProductionTaxExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Depreciation, depletion and amortization |  |  |  |  |  |  |  |  | 412,334,000 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 307,055,000 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 206,734,000 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Exploration expenses |  |  |  |  |  |  |  |  | 3,064,000 us-gaap_ExplorationExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 2,260,000 us-gaap_ExplorationExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 3,250,000 us-gaap_ExplorationExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Impairment of oil and gas properties |  |  |  |  |  |  |  |  | 47,238,000 us-gaap_ImpairmentOfOilAndGasProperties / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 1,168,000 us-gaap_ImpairmentOfOilAndGasProperties / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 3,581,000 us-gaap_ImpairmentOfOilAndGasProperties / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
General and administrative expenses |  |  |  |  |  |  |  |  | 68,778,000 us-gaap_GeneralAndAdministrativeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 61,266,000 us-gaap_GeneralAndAdministrativeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 44,599,000 us-gaap_GeneralAndAdministrativeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Total expenses |  |  |  |  |  |  |  |  | 908,047,000 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 623,557,000 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 397,084,000 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Gain on sale of properties |  |  |  |  |  |  |  |  | 186,999,000 us-gaap_GainLossOnSaleOfProperty / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember |  |
Operating income |  |  |  |  |  |  |  |  | 669,180,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 518,442,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 289,584,000 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Other income (expense) |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on derivative instruments |  |  |  |  |  |  |  |  | 327,011,000 us-gaap_DerivativeGainLossOnDerivativeNet / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | (35,432,000)us-gaap_DerivativeGainLossOnDerivativeNet / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 34,164,000 us-gaap_DerivativeGainLossOnDerivativeNet / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Interest expense, net of capitalized interest |  |  |  |  |  |  |  |  | (11,160,000)us-gaap_InterestExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | (7,502,000)us-gaap_InterestExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | (2,492,000)us-gaap_InterestExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Other income (expense) |  |  |  |  |  |  |  |  | 190,000 us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 1,551,000 us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 3,742,000 us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Total other income (expense) |  |  |  |  |  |  |  |  | 316,041,000 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | (41,383,000)us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 35,414,000 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Income before income taxes |  |  |  |  |  |  |  |  | 985,221,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 477,059,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 324,998,000 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Income tax benefit (expense) |  |  |  |  |  |  |  |  | (371,620,000)us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | (177,600,000)us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | (122,074,000)us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Net income |  |  |  |  |  |  |  |  | 613,601,000 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 299,459,000 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember | 202,924,000 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_GuarantorSubsidiariesMember
Intercompany Eliminations [Member] |  |  |  |  |  |  |  |  |  |  |
Other income (expense) |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  |  |  |  |  |  |  | (613,601,000)oas_EquityInEarningsInSubsidiaries / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember | (299,459,000)oas_EquityInEarningsInSubsidiaries / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember | (202,924,000)oas_EquityInEarningsInSubsidiaries / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember
Total other income (expense) |  |  |  |  |  |  |  |  | (613,601,000)us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember | (299,459,000)us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember | (202,924,000)us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember
Income before income taxes |  |  |  |  |  |  |  |  | (613,601,000)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember | (299,459,000)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember | (202,924,000)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember
Net income |  |  |  |  |  |  |  |  | $ (613,601,000)us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember | $ (299,459,000)us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember | $ (202,924,000)us-gaap_NetIncomeLoss / dei_LegalEntityAxis = us-gaap_ConsolidationEliminationsMember

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- Definition Exploration expenses (including prospecting) related to oil and gas producing entities and would be included in operating expenses of that entity. Costs incurred in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: (i) Costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. (ii) Costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, and the maintenance of land and lease records. (iii) Dry hole contributions and bottom hole contributions. (iv) Costs of drilling and equipping exploratory wells. (v) Costs of drilling exploratory-type stratigraphic test wells. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 25 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6474861&loc=d3e64954-109465 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)(15)) -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 15 -Article 4 + Details
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- Definition Amount of gain (loss) on sale or disposal of oil and gas property or timber property. + 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 + Details
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- Definition Cost incurred related to the gas activities, such as transportation, marketing and processing crude oil, natural gas and refined petroleum products. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e62136-109447 + Details
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- Definition The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.4) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
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- Definition The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced. + 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 932 -SubTopic 360 -Section 35 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28370743&loc=d3e66150-109466 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230 + Details
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- Definition Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(1)(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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