Oil And Natural Gas Properties And Related Equipment (Properties) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Oil And Natural Gas Properties And Related Equipment.
Proved property	$ 171,041	$ 170,750
Less: Accumulated depreciation, depletion, amortization and impairments	(117,055)	(115,704)
Oil and natural gas properties and equipment, net	$ 53,986	$ 55,046

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization of oil and gas property carried under the successful effort method. Oil and gas property include, but not limited to, the entity's wells and related equipment and facilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10.(b))
-URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862

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- Definition

Oil and gas properties net of accumulated depreciation, depletion, amortization, impairment, and abandonment, carried under the successful effort method.

+ References

+ Details

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- Definition

Oil and Gas properties with proved reserves under the successful effort method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-URI http://asc.fasb.org/subtopic&trid=2145654

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 25
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=96866604&loc=d3e64746-109465

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