Property And Equipment (Schedule Of Property And Equipment) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Oil and gas properties under the full cost method	$ 1,000,542	$ 1,453,329
Computers, furniture and fixtures	8,733us-gaap_FurnitureAndFixturesGross	8,734us-gaap_FurnitureAndFixturesGross
Total property and equipment	1,009,275us-gaap_PropertyPlantAndEquipmentGross	1,462,063us-gaap_PropertyPlantAndEquipmentGross
Accumulated depreciation, depletion and amortization	(539,766)	(389,912)
Net property and equipment	469,509us-gaap_PropertyPlantAndEquipmentNet	1,072,151us-gaap_PropertyPlantAndEquipmentNet
Subject To Amortization [Member]
Property, Plant and Equipment [Line Items]
Oil and gas properties under the full cost method	989,758	1,084,669
Not Subject To Amortization [Member] \| Incurred in 2014 [Member]
Property, Plant and Equipment [Line Items]
Oil and gas properties under the full cost method	945
Not Subject To Amortization [Member] \| Incurred in 2013 [Member]
Property, Plant and Equipment [Line Items]
Oil and gas properties under the full cost method	774	52,748
Not Subject To Amortization [Member] \| Incurred in 2012 [Member]
Property, Plant and Equipment [Line Items]
Oil and gas properties under the full cost method	3,087	138,641
Not Subject To Amortization [Member] \| Incurred prior to 2012 [Member]
Property, Plant and Equipment [Line Items]
Oil and gas properties under the full cost method	$ 5,978	$ 177,271

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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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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Oil and gas properties, gross, carried under the full cost method.

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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

-Publisher FASB

-Name Accounting Standards Codification

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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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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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