BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) revenue_source geographic_area	Mar. 31, 2019 USD ($)
Accounting Policies [Line Items]
Number of revenue sources \| revenue_source	2
Number of geographic areas in which entity operates \| geographic_area	1
Oil
Accounting Policies [Line Items]
Sales	$ 116,300	$ 123,600
Natural Gas and NGL
Accounting Policies [Line Items]
Sales	13,900	9,100
Oil and Gas Sales
Accounting Policies [Line Items]
Sales	$ 130,196	$ 132,684
Oil and Gas Sales \| Sales \| Operator Concentration Risk \| Top Four Operators
Accounting Policies [Line Items]
Concentration risk percentage	53.00%	59.00%

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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