Property And Equipment (Schedule Of Property And Equipment) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Oil and Gas Properties Under the Full Cost Method	$ 927,903	$ 1,000,542
Computers, Furniture and Fixtures	8,733us-gaap_FurnitureAndFixturesGross	8,733us-gaap_FurnitureAndFixturesGross
Total Property and Equipment	936,636us-gaap_PropertyPlantAndEquipmentGross	1,009,275us-gaap_PropertyPlantAndEquipmentGross
Accumulated Depreciation, Depletion and Amortization	(592,901)	(539,766)
Net Property and Equipment	343,735us-gaap_PropertyPlantAndEquipmentNet	469,509us-gaap_PropertyPlantAndEquipmentNet
Proved Properties [Member]
Property, Plant and Equipment [Line Items]
Oil and Gas Properties Under the Full Cost Method	916,437	989,758
Unproved Properties, Incurred In 2015 [Member]
Property, Plant and Equipment [Line Items]
Oil and Gas Properties Under the Full Cost Method	682
Unproved Properties, Incurred In 2014 [Member]
Property, Plant and Equipment [Line Items]
Oil and Gas Properties Under the Full Cost Method	945	945
Unproved Properties, Incurred In 2013 [Member]
Property, Plant and Equipment [Line Items]
Oil and Gas Properties Under the Full Cost Method	774	774
Unproved Properties, Incurred Prior To 2013 [Member]
Property, Plant and Equipment [Line Items]
Oil and Gas Properties Under the Full Cost Method	$ 9,065	$ 9,065

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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