Derivative Instruments - Schedule of Outstanding Commodity Derivative Instruments (Details) $ in Thousands	1 Months Ended	3 Months Ended
May 08, 2018 MMBTU $ / bbl bbl	Mar. 31, 2018 USD ($) MMBTU $ / bbl $ / MMBTU bbl
Derivative [Line Items]
Fair value asset \| $		$ (169,357)
Crude Oil [Member] \| 2018 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl		11,029,000
Average swap price (in dollars per barrel)		51.92
Fair value asset \| $		$ (125,062)
Crude Oil [Member] \| 2018 Two-way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl		825,000
Average floor price (in dollars per barrel)		48.67
Average ceiling price (in dollars per barrel)		53.07
Fair value asset \| $		$ (8,649)
Crude Oil [Member] \| 2019 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl		5,489,000
Average swap price (in dollars per barrel)		53.05
Fair value asset \| $		$ (32,612)
Crude Oil [Member] \| 2019 Two-way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl		93,000
Average floor price (in dollars per barrel)		48.67
Average ceiling price (in dollars per barrel)		53.07
Fair value asset \| $		$ (812)
Crude Oil [Member] \| 2019 Three-way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl		2,004,000
Average sub-floor price (in dollars per barrel)		40.00
Average floor price (in dollars per barrel)		50.00
Average ceiling price (in dollars per barrel)		65.99
Fair value asset \| $		$ (2,217)
Crude Oil [Member] \| 2020 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl		403,000
Average swap price (in dollars per barrel)		53.47
Fair value asset \| $		$ (1,261)
Crude Oil [Member] \| 2020 Three-way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl		186,000
Average sub-floor price (in dollars per barrel)		40.00
Average floor price (in dollars per barrel)		50.00
Average ceiling price (in dollars per barrel)		65.99
Fair value asset \| $		$ (113)
Natural Gas [Member] \| 2018 Swaps [Member]
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) \| MMBTU		6,325,000
Average swap price (in dollars per barrel) \| $ / MMBTU		3.05
Fair value asset \| $		$ 1,369
Subsequent Event [Member] \| Crude Oil [Member] \| 2018 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	826,000
Average floor price (in dollars per barrel)	56.79
Subsequent Event [Member] \| Crude Oil [Member] \| 2019 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	1,641,000
Subsequent Event [Member] \| Crude Oil [Member] \| 2020 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	124,000
Subsequent Event [Member] \| Natural Gas [Member] \| 2018 Swaps [Member]
Derivative [Line Items]
Average floor price (in dollars per barrel)	2.93
Subsequent Event [Member] \| Natural Gas [Member] \| 2018 Two-way Collars [Member]
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) \| MMBTU	1,104,000
Subsequent Event [Member] \| Natural Gas [Member] \| 2019 Three-way Collars [Member]
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) \| MMBTU	540,000

Derivative, Sub-Floor Price

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- Definition

The average cap rate on a group of price risk derivatives such as caps or collars. A payment or receipt is triggered if the market rate exceeds the cap rate on the contract.

+ References

No definition available.

+ Details

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- Definition

The average floor rate on a group of price risk derivatives such as floors or collars. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

+ References

No definition available.

+ Details

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Nominal energy measure used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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- Definition

Average fixed price related to the group of price risk swap derivatives.

+ References

No definition available.

+ Details

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