Related parties - Summary (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020 USD ($) contract	Sep. 30, 2019 USD ($) contract
Related Party Transaction [Line Items]
Capital expenditures for oil and natural gas properties	$ 278,277	$ 368,182
Helmerich & Payne, Inc. | Affiliated entity
Related Party Transaction [Line Items]
Capital expenditures for oil and natural gas properties	$ 18,104	$ 10,828
Helmerich & Payne, Inc. | Affiliated entity | Drilling Rig Contract - Long-Term Operating Lease
Related Party Transaction [Line Items]
Number of drilling rig contracts accounted for as long-term operating lease | contract	1	1
Halliburton | Affiliated entity
Related Party Transaction [Line Items]
Capital expenditures for oil and natural gas properties	$ 51,393