Buyer's Assumption of ARO

No definition available.

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- Definition

Capitalized costs oil and gas producing activities, total.

+ References

No definition available.

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- Definition

Discount rate for estimated future net revenues from proved properties.

+ References

No definition available.

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- Definition

Percentage of working interest interest in wells.

+ References

No definition available.

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- Definition

Supervision fees.

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No definition available.

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- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- References

No definition available.

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- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

The sum of amounts currently receivable other than from customers. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

+ References

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- Definition

Portion of accounts receivable attributable to joint interest partners in oil and gas properties. These are billings to the non-operators associated with the operation of wells and are based on those owners' working interests in the wells.

+ References

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

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- Definition

Amount due from parties in nontrade transactions, classified as other.

+ References

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- Definition

The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

Liability for amount due employees, in addition to wages and any other money that employers owe employees, when their employment ends through a layoff or other termination. For example, a company may provide involuntarily terminated employees with a lump sum payment equal to one week's salary for every year of employment.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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-Name Accounting Standards Codification
-Topic 505
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Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands				4 Months Ended	8 Months Ended	12 Months Ended
	Jan. 24, 2018	Dec. 31, 2016	Apr. 15, 2016	Apr. 22, 2016	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2015	Sep. 30, 2016
Summary of Significant Accounting Policies (Textual) [Abstract]
Proceeds from Sale of Oil and Gas Property and Equipment			$ 46,900
Discount rate for estimated future net revenues from proved properties						10.00%
Allowance for doubtful accounts receivable, current		$ 100			$ 100	$ 100
Accounts receivable from oil and gas sales		12,600			12,600	20,100
Accounts receivable related to joint interest owners		2,700			2,700	2,100
Severance tax credit receivables		1,600			1,600	2,100
Other receivables		$ 600			600	$ 3,000
Percentage of working interest in wells						100.00%
Supplemental Unemployment Benefits, Severance Benefits								$ 2,100
Lease commitments subject to capitalization						$ 6,200
Equipment lease term						3 years 5 months
Office Lease [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Lease commitments subject to capitalization						$ 2,000
Minimum [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Property, Plant and Equipment, Useful Life						2 years
Maximum [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Property, Plant and Equipment, Useful Life						20 years
Predecessor [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Total capitalized internal costs				$ 2,900			$ 12,700
Write-down of oil and gas properties				77,732			1,562,086
Total amount of supervision fees charged to wells				$ 2,700			$ 9,200
Treasury Stock, Shares, Acquired				65,170			70,437
Predecessor [Member] \| Shell Oil Company Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage				19.00%			16.00%
Predecessor [Member] \| Kinder Morgan Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage				20.00%			27.00%
Predecessor [Member] \| Plains Marketing Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage				14.00%			18.00%
Predecessor [Member] \| Howard Energy Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage				11.00%			13.00%
Predecessor [Member] \| Southcross Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage				11.00%			0.00%
Successor [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Total capitalized internal costs					5,400	$ 4,600
Write-down of oil and gas properties					133,496	0
Total amount of supervision fees charged to wells					$ 4,500	$ 4,700
Treasury Stock, Shares, Acquired					22,485	28,279
Successor [Member] \| Shell Oil Company Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage					15.00%	0.00%
Successor [Member] \| Kinder Morgan Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage					38.00%	48.00%
Successor [Member] \| Plains Marketing Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage					14.00%	0.00%
Successor [Member] \| Howard Energy Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage					0.00%	0.00%
Successor [Member] \| Southcross Concentration Risk [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Concentration risk, percentage					0.00%	0.00%
Building [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Equipment lease term		4 years
Subsequent Event [Member] \| AWP Olmos Sale [Member]
Summary of Significant Accounting Policies (Textual) [Abstract]
Proceeds from Sale of Oil and Gas Property and Equipment	$ 28,800
Buyer's Assumption of ARO	$ 6,200