Oil And Gas Properties (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Oil And Gas Properties [Abstract]
Oil and gas properties, at cost	$ 49,388	$ 45,101
Unevaluated properties, at cost	462	736
Accumulated depreciation, depletion and amortization	(24,437)	(21,714)
Oil and gas properties, net	25,413	24,123
Depletion expense	$ 2,800us-gaap_DepletionOfOilAndGasProperties	$ 2,600us-gaap_DepletionOfOilAndGasProperties	$ 3,000us-gaap_DepletionOfOilAndGasProperties

Oil And Gas Property Unevaluated Properties

No definition available.

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- Details

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- Definition

The noncash expense charged against earnings to recognize the consumption of oil and gas reserves that are part of an entities' assets.

+ 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

Depletion of oil and gas property carried under the full cost method.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Oil and gas properties, net of depletion, carried under the full cost method.

+ References

No definition available.

+ Details

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Period Type:	instant