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Oil and Gas Reserves Information (Unaudited) (Tables) | 12 Months Ended
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Dec. 31, 2020
Extractive Industries [Abstract] |
Summary of Changes in Net Quantities of Crude Oil and Natural Gas Reserves | Set forth below is a summary of the Company's proved oil and natural gas reserves:
| Predecessor |  |  | Successor
| Period from January 1, 2018 through August 13, 2018 |  |  | Period from August 14, 2018 through December 31, 2018 |  | Year Ended December 31, 2019 |  | Year Ended December 31, 2020
| Oil (MBbls) |  | Natural Gas (MMcf) |  |  | Oil (MBbls) |  | Natural Gas (MMcf) |  | Oil (MBbls) |  | Natural Gas (MMcf) |  | Oil (MBbls) |  | Natural Gas (MMcf)
Proved Reserves: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning of period (1) | 7,552 |  |  | 1,116,956 |  |  |  | 28,994 |  |  | 2,246,501 |  |  | 23,612 |  |  | 2,282,758 |  |  | 16,747 |  |  | 5,341,497 |
Revisions of previous estimates | 4 |  |  | 17,778 |  |  |  | 5 |  |  | 23,949 |  |  | (4,621) |  |  | 62,697 |  |  | (4,241) |  |  | 306,552 |
Extensions and discoveries | 5,651 |  |  | 950,032 |  |  |  | — |  |  | 30,126 |  |  | 259 |  |  | 315,286 |  |  | 2 |  |  | 365,663 |
Acquisitions of minerals in place | — |  |  | 220,088 |  |  |  | — |  |  | 33,612 |  |  | 240 |  |  | 3,023,109 |  |  | — |  |  | — |
Sales of minerals in place | (6,870) |  |  | (54,341) |  |  |  | (4,002) |  |  | (6,399) |  |  | (58) |  |  | (49,520) |  |  | — |  |  | — |
Production | (287) |  |  | (55,240) |  |  |  | (1,385) |  |  | (45,031) |  |  | (2,685) |  |  | (292,833) |  |  | (1,508) |  |  | (450,836) |
End of period | 6,050 |  |  | 2,195,273 |  |  |  | 23,612 |  |  | 2,282,758 |  |  | 16,747 |  |  | 5,341,497 |  |  | 11,000 |  |  | 5,562,876 |
Proved Developed Reserves: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning of period (1) | 7,552 |  |  | 436,114 |  |  |  | 22,845 |  |  | 550,198 |  |  | 21,466 |  |  | 583,107 |  |  | 15,104 |  |  | 1,890,357 |
End of period | 403 |  |  | 500,031 |  |  |  | 21,466 |  |  | 583,107 |  |  | 15,104 |  |  | 1,890,357 |  |  | 11,000 |  |  | 1,967,288 |
Proved Undeveloped Reserves: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning of period (1) | — |  |  | 680,842 |  |  |  | 6,149 |  |  | 1,696,303 |  |  | 2,146 |  |  | 1,699,651 |  |  | 1,643 |  |  | 3,451,140 |
End of period | 5,647 |  |  | 1,695,242 |  |  |  | 2,146 |  |  | 1,699,651 |  |  | 1,643 |  |  | 3,451,140 |  |  | — |  |  | 3,595,588 |
___________ (1)The beginning proved reserves balance at August 14, 2018 represents the contributed Bakken shale properties and the reserves of the Predecessor on a combined basis.
Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Reserves | The following table sets forth the standardized measure of discounted future net cash flows relating to proved reserves:
| Predecessor |  |  | Successor
| As of August 13, 2018 |  |  | As of December 31, 2018 |  | As of December 31, 2019 |  | As of December 31, 2020
| (In thousands)
Cash Flows Relating to Proved Reserves: |  |  |  |  |  |  |  |
Future Cash Flows | $ | 6,384,203 |  |  |  | $ | 8,054,092 |  |  | $ | 13,078,155 |  |  | $ | 9,871,616 |
Future Costs: |  |  |  |  |  |  |  |
Production | (1,804,559) |  |  |  | (2,160,912) |  |  | (3,562,042) |  |  | (3,173,350) |
Development and Abandonment | (1,945,141) |  |  |  | (1,800,335) |  |  | (3,171,351) |  |  | (2,592,520) |
Future Income Taxes | (199,589) |  |  |  | (622,241) |  |  | (676,759) |  |  | (154,872) |
Future Net Cash Flows | 2,434,914 |  |  |  | 3,470,604 |  |  | 5,668,003 |  |  | 3,950,874 |
10% Discount Factor | (1,556,927) |  |  |  | (1,996,764) |  |  | (2,754,792) |  |  | (2,015,149) |
Standardized Measure of Discounted Future Net Cash Flows | $ | 877,987 |  |  |  | $ | 1,473,840 |  |  | $ | 2,913,211 |  |  | $ | 1,935,725 |
Changes in Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Reserves | The following table sets forth the changes in the standardized measure of discounted future net cash flows relating to proved reserves:
| Predecessor |  |  | Successor
| For the Period from January 1, 2018 through August 13, 2018 |  |  | For the Period from August 14, 2018 through December 31, 2018 |  | Year Ended December 31, 2019 |  | Year Ended December 31, 2020
| (In thousands)
Standardized Measure, Beginning of Year | $ | 881,544 |  |  |  | $ | 1,317,383 |  |  | $ | 1,473,840 |  |  | $ | 2,913,211 |
Net change in sales price, net of production costs | (61,662) |  |  |  | 223,731 |  |  | (716,930) |  |  | (1,858,026) |
Development costs incurred during the year which were previously estimated | 86,086 |  |  |  | 112,073 |  |  | 311,331 |  |  | 302,135 |
Revisions of quantity estimates | 19,815 |  |  |  | 27,090 |  |  | 16,340 |  |  | 215,268 |
Accretion of discount | 53,413 |  |  |  | 55,692 |  |  | 175,514 |  |  | 326,074 |
Changes in future development and abandonment costs | (27,489) |  |  |  | 23,139 |  |  | (93,476) |  |  | 313,191 |
Changes in timing and other | (17,723) |  |  |  | 9,434 |  |  | 180,314 |  |  | (127,663) |
Extensions and discoveries | 167,986 |  |  |  | 15,263 |  |  | 442,099 |  |  | 180,624 |
Acquisitions of minerals in place | 72,738 |  |  |  | 54,143 |  |  | 1,813,491 |  |  | — |
Sales of minerals in place | (124,083) |  |  |  | (42,870) |  |  | (51,070) |  |  | — |
Sales, net of production costs | (129,991) |  |  |  | (181,218) |  |  | (580,922) |  |  | (612,194) |
Net changes in income taxes | (42,647) |  |  |  | (140,020) |  |  | (57,320) |  |  | 283,105 |
Standardized Measure, End of Year | $ | 877,987 |  |  |  | $ | 1,473,840 |  |  | $ | 2,913,211 |  |  | $ | 1,935,725 |
Summary of Prices Used in Determining Oil and Natural Gas Reserves Quantities and Cash Flows | Prices used in determining oil and natural gas reserves quantities and cash flows are as follows:
| Predecessor |  |  | Successor
| For the Period from January 1, 2018 through August 13, 2018 |  |  | For the Period from August 14, 2018 through December 31, 2018 |  | Year Ended December 31, 2019 |  | Year Ended December 31, 2020
Crude Oil: $/barrel | $ | 62.29 |  |  |  | $ | 61.21 |  |  | $ | 55.69 |  |  | $ | 39.57 |
Natural Gas: $/Mcf | $ | 2.74 |  |  |  | $ | 2.90 |  |  | $ | 2.58 |  |  | $ | 1.99 |

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- Definition Tabular disclosure of oil and gas sale price and production cost, including, but not limited to, average sale price and production cost per unit. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1204 + Details
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- Definition Tabular disclosure of the net quantities of an enterprise's interests in proved developed and undeveloped reserves of (a) crude oil (including condensate and natural gas liquids), (b) natural gas (including coal bed methane), (c) synthetic oil, (d) synthetic gas, and (e) other nonrenewable natural resources that are intended to be upgraded during the period as of the beginning of the period, changes in quantities during the period, and as of the end of the period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61884-109447 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61858-109447 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61872-109447 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61797-109447 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61869-109447 + Details
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- Definition Tabular disclosure of the future net cash flows relating to proved oil and gas reserves and oil and gas subject to purchase under long-term agreements in which the enterprise participates in the operation of the properties on which the oil and gas is located or otherwise serves as the producer. This information is presented in aggregate and for each geographic area for which reserve quantities are disclosed. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62476-109447 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 36 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62536-109447 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63094-109448 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62424-109447 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62479-109447 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62455-109447 + Details
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