XML 67 R90.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

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

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | srt_IncreaseDecreaseInProvedDevelopedAndUndevelopedReservesRollForward
Namespace Prefix: | srt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Energy measure of increase in quantity of proved reserve of oil and gas resulting from the extension of the proved acreage of previously discovered reservoir or discovery of new field with proved reserve or of new reservoir of proved reserve in old field, stated in a unit of energy. For example, but not limited to, barrel of oil equivalents (BOE) or one thousand cubic feet of natural gas equivalent (Mcfe). + 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 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReserveExtensionAndDiscoveryEnergy
Namespace Prefix: | srt_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | duration

X
- Definition Energy measure of proved reserve of oil and gas, stated in a unit of energy. For example, but not limited to, barrel of oil equivalents (BOE) or one thousand cubic feet of natural gas equivalent (Mcfe). + 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/2003/role/disclosureRef -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 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReserveNetEnergy
Namespace Prefix: | srt_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | instant

X
- Definition Energy measure of decrease in quantity of proved reserve of oil and gas resulting from production, stated in a unit of energy. For example, but not limited to, barrel of oil equivalents (BOE) or one thousand cubic feet of natural gas equivalent (Mcfe). + 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 5 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReserveProductionEnergy
Namespace Prefix: | srt_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | duration

X
- Definition Energy measure of increase in quantity of proved reserve of oil and gas resulting from purchase of mineral in place, stated in a unit of energy. For example, but not limited to, barrel of oil equivalents (BOE) or one thousand cubic feet of natural gas equivalent (Mcfe). + 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 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReservePurchaseOfMineralInPlaceEnergy
Namespace Prefix: | srt_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | duration

X
- Definition Energy measure of increase (decrease) in quantity of proved reserve of oil and gas related to revision of a previous estimate resulting from new information, except for an increase in proved acreage, or change in economic factors, stated in a unit of energy. For example, but not limited to, barrel of oil equivalents (BOE) or one thousand cubic feet of natural gas equivalent (Mcfe). + 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 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReserveRevisionOfPreviousEstimateEnergy
Namespace Prefix: | srt_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | duration

X
- Definition Additions to proved reserves that result from (1) extension of the proved acreage of previously discovered (old) reservoirs through additional drilling in periods after discovery and (2) discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields. + 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/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReservesExtensionsDiscoveriesAndAdditions
Namespace Prefix: | srt_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | duration

X
- Definition The net quantity of proved reserves as of the balance sheet date. Proved oil reserves are the estimated quantities of crude oil and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable. + 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/2003/role/disclosureRef -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 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReservesNet
Namespace Prefix: | srt_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | instant

X
- Definition Production of proved reserves. + 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/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReservesProduction
Namespace Prefix: | srt_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | duration

X
- Definition Purchase of minerals in place. + 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/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReservesPurchasesOfMineralsInPlace
Namespace Prefix: | srt_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revisions represent changes in previous estimates of proved reserves, either upward or downward, resulting from new information (except for an increase in proved acreage) normally obtained from development drilling and production history or resulting from change in economic factors. + 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/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReservesRevisionsOfPreviousEstimatesIncreaseDecrease
Namespace Prefix: | srt_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | duration

X
- Definition Energy measure of decrease in quantity of proved reserve of oil and gas resulting from sale of mineral in place, stated in a unit of energy. For example, but not limited to, barrel of oil equivalents (BOE) or one thousand cubic feet of natural gas equivalent (Mcfe). + 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 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReservesSaleOfMineralInPlaceEnergy
Namespace Prefix: | srt_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | duration

X
- Definition Sales of minerals in place. + 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/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447 + Details
Name: | srt_ProvedDevelopedAndUndevelopedReservesSalesOfMineralsInPlace
Namespace Prefix: | srt_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | duration

X
- Definition Energy measure of interests in proved developed reserves of crude oil, including condensate and natural gas liquids, natural gas, synthetic oil and gas, or other nonrenewable natural resource that is intended to be upgraded into synthetic oil and gas. + 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/2003/role/disclosureRef -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 + Details
Name: | srt_ProvedDevelopedReservesBOE1
Namespace Prefix: | srt_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | instant

X
- Definition Net quantities of an enterprise's interests in proved developed reserves of either crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other nonrenewable natural resource that is intended to be upgraded into synthetic oil and gas as of the beginning and the end of the year. "Net" quantities of reserves include those relating to the enterprise's operating and nonoperating interests in properties. Quantities of reserves relating to royalty interests owned are included in "net" quantities if the necessary information is available to the enterprise. "Net" quantities does not include reserves relating to interests of others in properties owned by the enterprise. The unit of measure for reserve quantities is defined as "barrels" for oil and synthetic oil reserves or "cubic feet" or "cubic meters" for natural gas and synthetic gas reserves. + 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/2003/role/disclosureRef -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 + Details
Name: | srt_ProvedDevelopedReservesVolume
Namespace Prefix: | srt_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | instant

X
- Definition Energy measure of proved undeveloped reserves of crude oil, including condensate and natural gas liquids, natural gas, synthetic oil and gas, or other nonrenewable natural resource that is intended to be upgraded into synthetic oil and gas. + 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/2003/role/disclosureRef -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 + Details
Name: | srt_ProvedUndevelopedReserveBOE1
Namespace Prefix: | srt_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | instant

X
- Definition Net quantities of an enterprise's interests in proved undeveloped reserves of either crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other renewable natural resource that is intended to be upgraded into synthetic oil and gas as of the beginning and the end of the year. "Net" quantities of reserves include those relating to the enterprise's operating and nonoperating interests in properties. Quantities of reserves relating to royalty interests owned are included in "net" quantities if the necessary information is available to the enterprise. "Net" quantities does not include reserves relating to interests of others in properties owned by the enterprise. The unit of measure for reserve quantities is defined as "barrels" for oil and synthetic oil reserves or "cubic feet" or "cubic meters" for natural gas and synthetic gas reserves. + 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/2003/role/disclosureRef -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 + Details
Name: | srt_ProvedUndevelopedReserveVolume
Namespace Prefix: | srt_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | srt_ReserveQuantitiesByTypeOfReserveAxis=srt_OilReservesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ReserveQuantitiesByTypeOfReserveAxis=srt_NaturalGasLiquidsReservesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ReserveQuantitiesByTypeOfReserveAxis=srt_NaturalGasReservesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |