Disaggregation of oil, gas, and NGL production revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 423,165	$ 354,233
Revenue, Remaining Performance Obligation, Amount	0
Midland Basin [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	344,011	287,528
South Texas [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 79,154	$ 66,705
Revenue Benchmark [Member] \| Geographic Concentration Risk [Member]
Segment Reporting Information [Line Items]
Relative percentage	100.00%	100.00%
Revenue Benchmark [Member] \| Geographic Concentration Risk [Member] \| Midland Basin [Member]
Segment Reporting Information [Line Items]
Relative percentage	81.00%	81.00%
Revenue Benchmark [Member] \| Geographic Concentration Risk [Member] \| South Texas [Member]
Segment Reporting Information [Line Items]
Relative percentage	19.00%	19.00%
Oil production revenue [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 305,777	$ 291,693
Oil production revenue [Member] \| Midland Basin [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	286,105	276,136
Oil production revenue [Member] \| South Texas [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	19,672	15,557
Gas production revenue [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	89,658	40,710
Gas production revenue [Member] \| Midland Basin [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	57,806	11,334
Gas production revenue [Member] \| South Texas [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	31,852	29,376
NGL production revenue [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	27,730	21,830
NGL production revenue [Member] \| Midland Basin [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	100	58
NGL production revenue [Member] \| South Texas [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 27,630	$ 21,772

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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