Derivative Instruments - Schedule of Outstanding Commodity Derivative Instruments (Details) bbl in Thousands, MMBTU in Thousands, $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($) MMBTU $ / bbl $ / MMBTU bbl
Derivative [Line Items]
Fair value asset \| $	$ (18,720)
Oil [Member] \| 2017 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	2,428
Average swap price (in dollars per barrel)	49.98
Fair value asset \| $	$ (3,220)
Oil [Member] \| 2017 Two Way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	728
Average floor price (in dollars per barrel)	46.25
Average ceiling price (in dollars per barrel)	54.37
Fair value asset \| $	$ (576)
Oil [Member] \| 2017 Three Way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	546
Average sub-floor price (in dollars per barrel)	31.67
Average floor price (in dollars per barrel)	45.83
Average ceiling price (in dollars per barrel)	59.94
Fair value asset \| $	$ 42
Oil [Member] \| 2018 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	12,951
Average swap price (in dollars per barrel)	50.81
Fair value asset \| $	$ (13,746)
Oil [Member] \| 2018 Two Way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	1,250
Average floor price (in dollars per barrel)	48.19
Average ceiling price (in dollars per barrel)	53.33
Fair value asset \| $	$ (927)
Oil [Member] \| 2018 Three Way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	186
Average sub-floor price (in dollars per barrel)	31.67
Average floor price (in dollars per barrel)	45.83
Average ceiling price (in dollars per barrel)	59.94
Fair value asset \| $	$ 51
Oil [Member] \| 2019 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	3,423
Average swap price (in dollars per barrel)	50.83
Fair value asset \| $	$ (846)
Oil [Member] \| 2019 Two-way Collars [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	93
Average floor price (in dollars per barrel)	48.67
Average ceiling price (in dollars per barrel)	53.07
Fair value asset \| $	$ (25)
Oil [Member] \| 2020 Swaps [Member]
Derivative [Line Items]
Total notional amount of oil (in Bbls) \| bbl	217
Average swap price (in dollars per barrel) \| $ / MMBTU	50.82
Fair value asset \| $	$ 28
Natural Gas [Member] \| 2018 Swaps [Member]
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) \| MMBTU	2,024
Average swap price (in dollars per barrel) \| $ / MMBTU	3.30
Fair value asset \| $	$ 502
Natural Gas [Member] \| 2019 Swaps [Member]
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) \| MMBTU	6,205
Average swap price (in dollars per barrel) \| $ / MMBTU	3.05
Fair value asset \| $	$ (3)

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.

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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.

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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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