Acquisitions and divestiture of evaluated and unevaluated oil and natural gas properties - 2019 Business combination (Details) - Acquired evaluated and unevaluated oil and natural gas properties in Glasscock County, Texas $ in Thousands	Dec. 06, 2019 USD ($)
Business Acquisition [Line Items]
Total assets acquired	$ 67,349
Asset retirement obligations	(2,728)
Net assets acquired	64,621
Cash consideration	64,621
Evaluated oil and natural gas properties
Business Acquisition [Line Items]
Property, plant, and equipment acquired	29,921
Unevaluated oil and natural gas properties
Business Acquisition [Line Items]
Property, plant, and equipment acquired	34,700
Asset retirement cost
Business Acquisition [Line Items]
Property, plant, and equipment acquired	$ 2,728