Derivative Instruments (Schedule of Natural Gas Derivative Positions) (Details) - Natural Gas	Jun. 30, 2019 MMBTU / d $ / MMBTU
3Q 2019 \| Basis Swaps
Derivative [Line Items]
Derivative, Volumes (in MMBtu/d) \| MMBTU / d	42,500
Weighted Average Fixed Price ($/MMBtu) \| $ / MMBTU	(1.49)
3Q 2019 \| Call Option
Derivative [Line Items]
Derivative, Volumes (in MMBtu/d) \| MMBTU / d	33,000
Weighted Average Ceiling Price ($/MMBtu) \| $ / MMBTU	3.25
4Q 2019 \| Basis Swaps
Derivative [Line Items]
Derivative, Volumes (in MMBtu/d) \| MMBTU / d	42,500
Weighted Average Fixed Price ($/MMBtu) \| $ / MMBTU	(1.30)
4Q 2019 \| Call Option
Derivative [Line Items]
Derivative, Volumes (in MMBtu/d) \| MMBTU / d	33,000
Weighted Average Ceiling Price ($/MMBtu) \| $ / MMBTU	3.25
FY 2020 \| Basis Swaps
Derivative [Line Items]
Derivative, Volumes (in MMBtu/d) \| MMBTU / d	29,541
Weighted Average Fixed Price ($/MMBtu) \| $ / MMBTU	(0.77)
FY 2020 \| Call Option
Derivative [Line Items]
Derivative, Volumes (in MMBtu/d) \| MMBTU / d	33,000
Weighted Average Ceiling Price ($/MMBtu) \| $ / MMBTU	3.50

- Definition

Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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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

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

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

+ References

No definition available.

+ Details

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