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Supplemental Oil and Natural Gas Information (Unaudited) - Schedule of Standardized Measure of Future Net Cash Flows (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Oil and Gas Exploration and Production Industries Disclosures [Abstract]    
Standardized measure, beginning of year $ 10,348 $ 11,599
Sales of oil and natural gas, net of production costs (627) (4,296)
Net changes in prices and production costs (8,487) (2,499)
Changes in estimated future development costs (302)
Extensions and discoveries 2,231
Purchases of minerals in place 5,841
Sale of minerals in place (83)
Revisions in previous quantity estimates (1,148) 2,130
Previously estimated development costs incurred
Net changes in income taxes 1,649 (299)
Accretion of discount 855 1,068
Changes in timing and other 457 497
Standardized measure, end of year $ 8,586 $ 10,348