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Supplemental Oil and Gas Reserve Information - Discounted Future Cash Flows Relating to Proved Reserves and Disclosures (Details) $ in Thousands | Dec. 31, 2020 USD ($)
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Oil and Gas Exploration and Production Industries [Line Items] |
Future cash inflows | $ 5,197,220
Future production costs | 2,792,921
Future development costs | 610,658
Future outflows for income tax | 232,849
Future net cash flows | 1,560,792
10% annual discount for estimated timing of cash flows | 611,915
Standardized measure of discounted future net cash flows | 948,877
Pro Forma |
Oil and Gas Exploration and Production Industries [Line Items] |
Future cash inflows | 6,249,050
Future production costs | 3,738,979
Future development costs | 590,227
Future outflows for income tax | 179,121
Future net cash flows | 1,740,723
10% annual discount for estimated timing of cash flows | 600,711
Standardized measure of discounted future net cash flows | 1,140,012
Permian Basin Sale |
Oil and Gas Exploration and Production Industries [Line Items] |
Future cash inflows | (1,010,896)
Future production costs | (404,546)
Future development costs | (177,445)
Future outflows for income tax | (64,673)
Future net cash flows | (364,232)
10% annual discount for estimated timing of cash flows | (203,962)
Standardized measure of discounted future net cash flows | (160,270)
Williston Basin Acquisition |
Oil and Gas Exploration and Production Industries [Line Items] |
Future cash inflows | 2,062,726
Future production costs | 1,350,604
Future development costs | 157,014
Future outflows for income tax | 10,945
Future net cash flows | 544,163
10% annual discount for estimated timing of cash flows | (192,758)
Standardized measure of discounted future net cash flows | $ 351,405

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