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Supplemental Information on Oil and Gas Producing Activities - Capitalized Costs Relating to Oil and Gas Producing Activities (Detail) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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| Capitalized Costs Relating to Oil and Gas Producing Activities: | ||||||||
| Properties not being amortized | $ 47,290us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationCumulative | $ 88,194us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationCumulative | $ 66,794us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationCumulative | |||||
| Properties being amortized | 347,186us-gaap_CapitalizedCostsAssetRetirementCosts | [1] | 222,032us-gaap_CapitalizedCostsAssetRetirementCosts | [1] | 195,329us-gaap_CapitalizedCostsAssetRetirementCosts | [1] | ||
| Total capitalized costs | 394,476us-gaap_CapitalizedCostsOilAndGasProducingActivitiesGross | 310,226us-gaap_CapitalizedCostsOilAndGasProducingActivitiesGross | 262,123us-gaap_CapitalizedCostsOilAndGasProducingActivitiesGross | |||||
| Less accumulated depreciation, depletion, and amortization | (289,272)us-gaap_CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities | (171,854)us-gaap_CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities | (155,681)us-gaap_CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities | |||||
| Net capitalized costs | $ 105,204us-gaap_CapitalizedCostsOilAndGasProducingActivitiesNet | $ 138,372us-gaap_CapitalizedCostsOilAndGasProducingActivitiesNet | $ 106,442us-gaap_CapitalizedCostsOilAndGasProducingActivitiesNet | |||||
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- Definition
Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The amount of asset retirement costs previously incurred and capitalized separately from the capitalized amount of the associated long-lived assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The sum of capitalized costs relating to oil and gas producing activities before accounting for accumulated depreciation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Net amount of capitalized costs relating to oil and gas producing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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