Percentage of overriding royalty interest carved out.

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Percentage of gross revenues to be received.

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- Definition

Percentage of limited partnership interest.

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- Definition

Percentage investment held in the general partner.

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- Definition

Proceeds from reimbursements related to oil and natural gas properties.

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Direct costs paid to a related party for expenses incurred in the operations of wells and gathering systems.

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Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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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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Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	2 Months Ended	3 Months Ended	5 Months Ended	7 Months Ended	12 Months Ended
	May 31, 2018	Mar. 31, 2018	May 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2011
Related Party Transaction [Line Items]
Percentage of general partnership interest	2.00%	2.00%	2.00%		2.00%	2.00%
Reimbursements related to oil and natural gas properties				$ 1,294
EnerVest, Ltd.
Related Party Transaction [Line Items]
Percentage of ownership interest in EV Energy GP, L.P. (EV Energy GP)	71.25%		71.25%
Predecessor
Related Party Transaction [Line Items]
Related party					$ 4,194
Percentage of general partnership interest					2.00%
Reimbursements related to oil and natural gas properties			$ 652		$ 2,517
Predecessor \| EnerVest, Ltd.
Related Party Transaction [Line Items]
Administrative fees paid to related party			7,200		14,100	$ 15,900
Direct expenses incurred and reimbursed to related party			8,400		20,100	21,200
Overriding royalty interests
Related Party Transaction [Line Items]
Percentage of overriding royalty interest carved out							7.50%
Percentage of limited partnership interest							48.00%
Percentage of gross revenues to be received							5.64%
Equity in (loss) income of unconsolidated affiliates			100		500	100
Dividends from unconsolidated affiliates			$ 300		$ 300	$ 100