Percent Of Assets Sold

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Properties Not Subject to Amortization

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Property Subject To Amortization

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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The capitalized costs incurred during the period (excluded from amortization) 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: 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. Exploration costs also include costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, the maintenance of land and lease records, dry hole contributions and bottom hole contributions, costs of drilling and equipping exploratory wells and costs of drilling exploratory-type stratigraphic test wells.

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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.

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Amount of interest capitalized during the period.

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-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

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Amount of standardized measure of discounted future net cash flow relating to proved oil and gas reserves.

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Difference of unusual or infrequent items gross less applicable insurance proceeds.

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Property And Equipment (Narrative) (Details) (USD $)	3 Months Ended		12 Months Ended			0 Months Ended
Property And Equipment (Narrative) (Details) (USD $)	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 08, 2013	Dec. 31, 2011
Business Acquisition [Line Items]
Properties not subject to amortization			$ 10,800,000end_PropertiesNotSubjectToAmortization
Property subject to amortization			397,000,000end_PropertySubjectToAmortization
Directly related employee costs capitalized			11,700,000us-gaap_ExplorationCosts	12,400,000us-gaap_ExplorationCosts	17,900,000us-gaap_ExplorationCosts
Exploration and development related capitalized costs			9,800,000us-gaap_InterestCostsCapitalized	24,000,000us-gaap_InterestCostsCapitalized	26,900,000us-gaap_InterestCostsCapitalized
Impairment of oil and gas properties	6,000,000us-gaap_ImpairmentOfOilAndGasProperties	3,500,000us-gaap_ImpairmentOfOilAndGasProperties	476,721,000us-gaap_ImpairmentOfOilAndGasProperties	9,566,000us-gaap_ImpairmentOfOilAndGasProperties	53,072,000us-gaap_ImpairmentOfOilAndGasProperties
Standard measure of discounted future net cash flows			523,735,000	535,682,000	498,978,000		264,872,000
Proceeds from insurance claim			13,000,000
Loss Of Production Income [Member]
Business Acquisition [Line Items]
Proceeds from insurance claim			10,800,000
Property Damage [Member]
Business Acquisition [Line Items]
Proceeds from insurance claim			2,200,000
Loss, Plug And Abandonement And Replacement Of E1Y Well [Member]
Business Acquisition [Line Items]
Proceeds from insurance claim			12,600,000
Samson Exploration LLC [Member]
Business Acquisition [Line Items]
Acquisition date			Nov. 08, 2013
Percentage of assets sold						50.00%
PUD Reserves Transfer [Member]
Business Acquisition [Line Items]
Standard measure of discounted future net cash flows			$ 75,000,000