Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Natural gas sales	$ 19,316	$ 3,939
Natural gas liquids sales	247
Oil sales	8,989	$ 2,983
Transportation and handling	734
Marketing gas sales	4,944
Total natural gas, natural gas liquids, and oil revenue	34,230
Appalachian Basin [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Natural gas sales	18,792
Natural gas liquids sales
Oil sales	1,537
Transportation and handling	734
Marketing gas sales	4,944
Total natural gas, natural gas liquids, and oil revenue	26,007
Ventura Basin [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Natural gas sales	524
Natural gas liquids sales	247
Oil sales	7,452
Transportation and handling
Marketing gas sales
Total natural gas, natural gas liquids, and oil revenue	$ 8,223

Revenue from storage facilities, such as a LNG ( Liquefied Natural Gas) storage facility.

No definition available.

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- Definition

Aggregate revenue during the period related to oil and gas business activities.

+ References

No definition available.

+ Details

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- Definition

Revenue from the sale of oil and gas during the period.

+ References

No definition available.

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- References

No definition available.

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- Definition

Expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services. Costs of public relations and corporate promotions are typically considered to be marketing costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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