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Supplemental Information on Oil and Natural Gas Producing Activities (Unaudited) - Summary of Changes in Estimated Oil and Natural Gas Reserves (Unaudited) (Details)
Mcf in Thousands
 12 Months Ended
Dec. 31, 2019
MBoe
Mcf
MBbls
Dec. 31, 2018
MBoe
Mcf
MBbls
Dec. 31, 2017
MBoe
MBbls
Mcf
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)      
Proved developed and undeveloped reserves, Beginning balance (MBoe) | MBoe 160,176 177,594 163,955
Revisions of previous estimates (MBoe) | MBoe (58,514) (33,188) 10,879
Acquisitions of new reserves (MBoe) | MBoe   15,350 202
Extensions and discoveries (MBoe) | MBoe 1,084 19,332 19,373
Sales of reserves in place (MBoe) | MBoe (905) (6,577) (1,909)
Production (MBoe) | MBoe (11,956) (12,335) (14,906)
Proved developed and undeveloped reserves, Ending balance (MBoe) | MBoe 89,885 160,176 177,594
Proved developed reserves (MBoe) | MBoe 62,086 92,303 123,765
Proved undeveloped reserves (MBoe) | MBoe 27,799 67,873 53,829
Oil      
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)      
Proved developed and undeveloped reserves, beginning balance 64,019 61,791 52,884
Revisions of previous estimates (25,530) (2,316) 804
Acquisitions of new reserves   2,146 18
Extensions and discoveries 635 11,148 12,446
Sales of reserves in place (297) (5,273) (204)
Production (3,519) (3,477) (4,157)
Proved developed and undeveloped reserves, ending balance 35,308 64,019 61,791
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) 14,078 18,693 25,845
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) 21,230 45,326 35,946
NGL      
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)      
Proved developed and undeveloped reserves, beginning balance 28,175 34,314 33,607
Revisions of previous estimates (9,277) (8,952) 2,628
Acquisitions of new reserves   4,131 70
Extensions and discoveries 94 2,320 1,914
Sales of reserves in place (223) (809) (529)
Production (2,910) (2,829) (3,376)
Proved developed and undeveloped reserves, ending balance 15,859 28,175 34,314
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) 14,532 22,302 29,922
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) 1,327 5,873 4,392
Natural gas      
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)      
Proved developed and undeveloped reserves, beginning balance | Mcf 407,891 488,932 464,782
Revisions of previous estimates | Mcf (142,239) (131,518) 44,679
Acquisitions of new reserves | Mcf   54,436 683
Extensions and discoveries | Mcf 2,127 35,185 30,080
Sales of reserves in place | Mcf (2,308) (2,969) (7,055)
Production | Mcf (33,164) (36,175) (44,237)
Proved developed and undeveloped reserves, ending balance | Mcf 232,307 407,891 488,932
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) | Mcf 200,853 307,845 407,988
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) | Mcf 31,454 100,046 80,944