Derivative Instruments and Hedging Activities - Outstanding Commodity Derivatives (Details)	9 Months Ended
Sep. 30, 2015 $ / Mcf MMcf
Natural Gas Collars with contract period of October 2015 - December 2015
Derivative [Line Items]
Volume (in mmcf) \| MMcf	17,900
Natural Gas Collars with contract period of October 2015 - December 2015 \| Minimum
Derivative [Line Items]
Collar Floor Price (in usd per Mcf)	3.86
Collar Ceiling Price (in usd per Mcf)	4.27
Natural Gas Collars with contract period of October 2015 - December 2015 \| Maximum
Derivative [Line Items]
Collar Floor Price (in usd per Mcf)	3.91
Collar Ceiling Price (in usd per Mcf)	4.43
Natural Gas Collars with contract period of October 2015 - December 2015 \| Weighted Average
Derivative [Line Items]
Collar Floor Price (in usd per Mcf)	3.87
Collar Ceiling Price (in usd per Mcf)	4.35
Natural Gas Swaps with contract period of October 2015 - December 2015
Derivative [Line Items]
Volume (in mmcf) \| MMcf	17,900
Natural Gas Swaps with contract period of October 2015 - December 2015 \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf)	3.92
Natural Gas Swaps with contract ending October 2015
Derivative [Line Items]
Volume (in mmcf) \| MMcf	4,500
Natural Gas Swaps with contract ending October 2015 \| Weighted Average
Derivative [Line Items]
Swaps Weighted Average (in usd per Mcf)	3.36

- 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

Name:	us-gaap_DerivativeCapPrice
Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	us-gaap_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeNonmonetaryNotionalAmountVolume
Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
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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Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

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- Details

Name:	us-gaap_RangeAxis=us-gaap_WeightedAverageMember
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- Details

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- Details

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