Derivative Instruments and Hedging Activities - Outstanding Commodity Derivatives (Details) bbl in Millions, Mcf in Millions	9 Months Ended
Sep. 30, 2016 $ / bbl $ / Mcf Mcf bbl
Natural Gas Swap With Contract Period of October 2016
Derivative [Line Items]
Volume (in mmcf for gas and mbbls for oil) \| Mcf	7.5
Swaps Weighted Average (in usd per Mcf or usd per bbl)	2.51
Natural Gas Swap With Contract Period of January 2017 to December 2017
Derivative [Line Items]
Volume (in mmcf for gas and mbbls for oil) \| Mcf	35.5
Swaps Weighted Average (in usd per Mcf or usd per bbl)	3.12
Natural Gas Collar With Contract Period of January 2017 to December 2017
Derivative [Line Items]
Volume (in mmcf for gas and mbbls for oil) \| Mcf	35.5
Natural Gas Collar With Contract Period of January 2017 to December 2017 \| Minimum
Derivative [Line Items]
Collar Ceiling Price (in usd per Mcf or usd per bbl)	3.42
Natural Gas Collar With Contract Period of January 2017 to December 2017 \| Maximum
Derivative [Line Items]
Collar Ceiling Price (in usd per Mcf or usd per bbl)	3.45
Natural Gas Collar With Contract Period of January 2017 to December 2017 \| Weighted Average
Derivative [Line Items]
Collar Floor Price (in usd per Mcf or usd per bbl)	3.09
Collar Ceiling Price (in usd per Mcf or usd per bbl)	3.43
Natural Gas Basis Swap With Contract Period of January 2018 to December 2019
Derivative [Line Items]
Volume (in mmcf for gas and mbbls for oil) \| Mcf	17.7
Swaps Weighted Average (in usd per Mcf or usd per bbl)	0.42
Crude Oil Collar With Contract Period Of July 2016 to December 2016
Derivative [Line Items]
Volume (in mmcf for gas and mbbls for oil) \| bbl	0.5
Crude Oil Collar With Contract Period Of July 2016 to December 2016 \| Minimum
Derivative [Line Items]
Collar Ceiling Price (in usd per Mcf or usd per bbl) \| $ / bbl	47.10
Crude Oil Collar With Contract Period Of July 2016 to December 2016 \| Maximum
Derivative [Line Items]
Collar Ceiling Price (in usd per Mcf or usd per bbl) \| $ / bbl	47.50
Crude Oil Collar With Contract Period Of July 2016 to December 2016 \| Weighted Average
Derivative [Line Items]
Collar Floor Price (in usd per Mcf or usd per bbl) \| $ / bbl	38.00
Collar Ceiling Price (in usd per Mcf or usd per bbl) \| $ / bbl	47.28

- Definition

The cap rate on a price risk derivative such as a cap or collar. 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

Floor rate on a price risk derivative such as a floor or a collar. 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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- 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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