A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- 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

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- 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

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- 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

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- 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

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- 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

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- 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

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- 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

+ Details

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- 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

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- 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

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- 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

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- 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

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- 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

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- 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

+ Details

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- 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

+ Details

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- 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

+ Details

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- 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

+ Details

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- Definition

Proved Developed and Undeveloped Reserves, (Energy) Impact of New Accounting Guidance

+ References

No definition available.

+ Details

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- Definition

Proved Developed and Undeveloped Reserves, Impact of New Accounting Guidance

+ References

No definition available.

+ Details

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- Details

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- Details

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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	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2016 MBoe MBbls Mcf	Oct. 01, 2016 MBoe Mcf MBbls	Dec. 31, 2018 MBoe MBbls Mcf	Dec. 31, 2017 MBoe Mcf MBbls	Dec. 31, 2016 MBoe MBbls Mcf	Dec. 31, 2015 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			177,600
Revisions of previous estimates (MBoe) \| MBoe			(24,900)	10,900	(105,400)
Acquisitions of new reserves (MBoe) \| MBoe			15,400
Extensions and discoveries (MBoe) \| MBoe			19,300	19,400	7,800
Sales of reserves in place (MBoe) \| MBoe			(6,600)	(1,900)	(24,600)
Proved developed and undeveloped reserves, Ending balance (MBoe) \| MBoe			160,200	177,600
Predecessor
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, Beginning balance (MBoe) \| MBoe	137,992	324,626			324,626
Adoption of ASU 2015-02 (MBoe) \| MBoe		(19,084)
Revisions of previous estimates (MBoe) \| MBoe		(130,709)
Extensions and discoveries (MBoe) \| MBoe		2,785
Sales of reserves in place (MBoe) \| MBoe		(24,598)
Production (MBoe) \| MBoe		(15,027)
Proved developed and undeveloped reserves, Ending balance (MBoe) \| MBoe		137,992
Proved developed reserves (MBoe) \| MBoe		126,121				260,498
Proved undeveloped reserves (MBoe) \| MBoe		11,872				64,129
Predecessor \| Oil
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, beginning balance	27,252	77,911			77,911
Adoption of ASU 2015-02		(6,971)
Revisions of previous estimates		(39,973)
Extensions and discoveries		987
Sales of reserves in place		(387)
Production		(4,315)
Proved developed and undeveloped reserves, ending balance		27,252
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)		24,541				48,639
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)		2,711				29,272
Predecessor \| Oil \| Non-controlling Interest
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, beginning balance		7,004			7,004
Predecessor \| NGL
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, beginning balance	33,019	61,075			61,075
Adoption of ASU 2015-02		(3,695)
Revisions of previous estimates		(21,475)
Extensions and discoveries		472
Sales of reserves in place		0
Production		(3,358)
Proved developed and undeveloped reserves, ending balance		33,019
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)		30,238				51,089
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)		2,781				9,986
Predecessor \| NGL \| Non-controlling Interest
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, beginning balance		3,694			3,694
Predecessor \| 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	466,328	1,113,840			1,113,840
Adoption of ASU 2015-02 \| Mcf		(50,508)
Revisions of previous estimates \| Mcf		(415,568)
Extensions and discoveries \| Mcf		7,955
Sales of reserves in place \| Mcf		(145,267)
Production \| Mcf		(44,124)
Proved developed and undeveloped reserves, ending balance \| Mcf		466,328
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) \| Mcf		428,050				964,617
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) \| Mcf		38,278				149,223
Predecessor \| Natural gas \| Non-controlling Interest
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, beginning balance \| Mcf		50,508			50,508
Successor
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, Beginning balance (MBoe) \| MBoe			177,594	163,955
Revisions of previous estimates (MBoe) \| MBoe	25,270		(33,188)	10,879
Acquisitions of new reserves (MBoe) \| MBoe			15,350	202
Extensions and discoveries (MBoe) \| MBoe	5,034		19,332	19,373
Sales of reserves in place (MBoe) \| MBoe			(6,577)	(1,909)
Production (MBoe) \| MBoe	(4,341)		(12,335)	(14,906)
Proved developed and undeveloped reserves, Ending balance (MBoe) \| MBoe	163,955		160,176	177,594	163,955
Proved developed reserves (MBoe) \| MBoe	120,706		92,303	123,765	120,706
Proved undeveloped reserves (MBoe) \| MBoe	43,249		67,873	53,829	43,249
Successor \| Oil
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, beginning balance			61,791	52,884
Revisions of previous estimates	23,978		(2,316)	804
Acquisitions of new reserves			2,146	18
Extensions and discoveries	2,868		11,148	12,446
Sales of reserves in place			(5,273)	(204)
Production	(1,214)		(3,477)	(4,157)
Proved developed and undeveloped reserves, ending balance	52,884		64,019	61,791	52,884
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)	25,911		18,693	25,845	25,911
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)	26,973		45,326	35,946	26,973
Successor \| NGL
Proved Developed and Undeveloped Reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)
Proved developed and undeveloped reserves, beginning balance			34,314	33,607
Revisions of previous estimates	1,139		(8,952)	2,628
Acquisitions of new reserves			4,131	70
Extensions and discoveries	448		2,320	1,914
Sales of reserves in place			(809)	(529)
Production	(999)		(2,829)	(3,376)
Proved developed and undeveloped reserves, ending balance	33,607		28,175	34,314	33,607
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)	29,290		22,302	29,922	29,290
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas)	4,317		5,873	4,392	4,317
Successor \| 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			488,932	464,782
Revisions of previous estimates \| Mcf	915		(131,518)	44,679
Acquisitions of new reserves \| Mcf			54,436	683
Extensions and discoveries \| Mcf	10,309		35,185	30,080
Sales of reserves in place \| Mcf			(2,969)	(7,055)
Production \| Mcf	(12,770)		(36,175)	(44,237)
Proved developed and undeveloped reserves, ending balance \| Mcf	464,782		407,891	488,932	464,782
Proved developed reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) \| Mcf	393,028		307,845	407,988	393,028
Proved undeveloped reserves (in MBbls for Oil and NGLs/MMcf for Natural Gas) \| Mcf	71,754		100,046	80,944	71,754