Derivative Financial Instruments (Details) - Price risk derivatives	1 Months Ended	12 Months Ended
Feb. 29, 2016 $ / bbl MBbls	Dec. 31, 2015 $ / bbl MBbls
Three-way Collars \| Term January 2016 to December 2016
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls		2,000
Weighted average floor price per Bbl		85.00
Weighted average ceiling price per Bbl		110.00
Weighted average purchased call price per Bbl		135.00
Three-way Collars \| Term January 2017 to December 2017
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls	2,000
Weighted average deferred premium payable per Bbl	1.68
Weighted average sold put price per Bbl	30.00
Weighted average floor price per Bbl	45.00
Weighted average ceiling price per Bbl	60.00
Three-way Collars \| Term January 2018 to December 2018
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls		913
Weighted average deferred premium payable per Bbl		2.37
Weighted average sold put price per Bbl		45.00
Weighted average floor price per Bbl		60.00
Weighted average ceiling price per Bbl		75.00
Purchased puts \| Term January 2016 to December 2016
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls		2,000
Weighted average deferred premium payable per Bbl		3.41
Weighted average floor price per Bbl		85.00
Swaps with puts \| Term January 2016 to December 2016
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls		2,000
Weighted average swap price per Bbl		75.00
Weighted average sold put price per Bbl		60.00
Swaps with puts \| Term January 2017 to December 2017
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls		2,000
Weighted average swap price per Bbl		64.95
Weighted average sold put price per Bbl		50.00
Sold calls \| Term January 2017 to December 2017
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls		2,000
Weighted average ceiling price per Bbl		85.00
Sold calls \| Term January 2018 to December 2018
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls	2,000
Weighted average ceiling price per Bbl	65.00
Sold calls \| Term January 2019 to December 2019
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls		913
Weighted average ceiling price per Bbl		80.00
Swap with puts/calls \| Term January 2017 to December 2017
Derivative Financial Instruments
Volumes (in MBbl) \| MBbls		2,000
Weighted average deferred premium payable per Bbl		2.13
Weighted average swap price per Bbl		72.50
Weighted average sold put price per Bbl		55.00
Weighted average purchased call price per Bbl		90.00

The average strike price on the group of purchased call price risk option contracts.

No definition available.

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- Definition

The average strike price on the group of sold put price risk option contracts.

+ References

No definition available.

+ Details

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- Definition

Represents the weighted average deferred premium per barrel of the derivative contracts expressed in dollars per barrel.

+ References

No definition available.

+ Details

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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

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.

+ 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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Data Type:	num:volumeItemType
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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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