Supplemental Oil And Gas Information (Schedule Of Capitalized Costs Related To Oil And Gas Producing Activities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Supplemental Oil And Gas Information [Abstract]
Proved oil and gas properties	$ 6,503	$ 5,704
Unproved properties	23
Total proved and unproved oil and gas properties	6,526	5,704
Less accumulated depreciation, depletion and amortization	(1,722)	(984)
Net oil and gas properties	$ 4,804	$ 4,720

Supplemental Oil And Gas Information [Abstract]

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- Definition

Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities.

+ 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

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- Definition

The sum of capitalized costs relating to oil and gas producing activities before accounting for accumulated depreciation.

+ References

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Net amount of capitalized costs relating to oil and gas producing activities.

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- Definition

Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table.

+ 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 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447

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- Definition

Capitalized costs of unproved properties incurred for any combination mineral interests acquisitions and other costs not previously disclosed within this table.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-URI http://asc.fasb.org/topic&trid=2145477

Reference 2: 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

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