The total fair value of shares issued during the period under a deferred compensation arrangement.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of new stock issued during the period.

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SHARE–BASED COMPENSATION (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		2 Months Ended	3 Months Ended	5 Months Ended	7 Months Ended	12 Months Ended
	Jun. 04, 2018	May 31, 2018	Mar. 31, 2018	May 31, 2018	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation cost					$ 1,227
Management Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units and/or rights that may be awarded under long-term incentive plan	689,362
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted					61,300
Weighted average fair value					$ 20.33
Restricted Stock \| Management Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value					$ 20.33
Units vested, fair value					$ 1,200
Shares forfeited					0
Number of shares available for grant					600,000	600,000
Share-based compensation cost					$ 1,100
Unrecognized compensation cost					$ 100	$ 100
Weighted average period					4 months 24 days
Restricted Stock \| Management Incentive Plan \| Central Texas Oil and Gas Properties [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted					54,800
Restricted Stock \| Board of Directors Chairman \| Management Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted					6,500
Series A Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation cost					$ 88
Deferred compensation arrangement with individual, fair value of shares issued					$ 200
Series A Preferred Stock \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued	21,000
Predecessor
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units and/or rights that may be awarded under long-term incentive plan		5,000,000		5,000,000
Share-based compensation cost				$ 3,784			$ 4,266	$ 6,611
Predecessor \| Unvested Phantom Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted		0	0				0
Weighted average fair value								$ 2.05
Units vested, fair value				$ 6,700			$ 6,300	$ 8,400
Shares forfeited				51,686
Share-based compensation cost				$ 1,000			$ 4,300	$ 6,600
Accelerated compensation cost				$ 2,800
Vesting period						4 years