Derivatives (Summary Of Derivative Instruments Contracts) (Details) | Jun. 30, 2018MMBTU$ / MMBTU$ / bblbbl |
Natural Gas Costless Collars [Member] | Derivative Contract Period One [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 40,000 |
Natural Gas Costless Collars [Member] | Derivative Contract Period One [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | $ / MMBTU | 2.75 |
Natural Gas Costless Collars [Member] | Derivative Contract Period One [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | $ / MMBTU | 3.35 |
Natural Gas Costless Collars [Member] | Derivative Contract Period Two [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 40,000 |
Natural Gas Costless Collars [Member] | Derivative Contract Period Two [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | $ / MMBTU | 2.75 |
Natural Gas Costless Collars [Member] | Derivative Contract Period Two [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | $ / MMBTU | 3.30 |
Natural Gas Costless Collars [Member] | Derivative Contract Period Three [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 50,000 |
Natural Gas Costless Collars [Member] | Derivative Contract Period Three [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | $ / MMBTU | 2.80 |
Natural Gas Costless Collars [Member] | Derivative Contract Period Three [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | $ / MMBTU | 3.15 |
Natural Gas Fixed Price Swaps | Derivative Contract Period Four [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 50,000 |
Contract price | $ / MMBTU | 3.080 |
Natural Gas Fixed Price Swaps | Derivative Contract Period Five [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 40,000 |
Contract price | $ / MMBTU | 2.910 |
Natural Gas Fixed Price Swaps | Derivative Contract Period Six [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 100,000 |
Contract price | $ / MMBTU | 2.835 |
Natural Gas Fixed Price Swaps | Derivative Contract Period Seven [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 100,000 |
Contract price | $ / MMBTU | 2.925 |
Natural Gas Fixed Price Swaps | Derivative Contract Period Eight [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 50,000 |
Contract price | $ / MMBTU | 2.988 |
Natural Gas Fixed Price Swaps | Derivative Contract Period Nine [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Natural Gas | MMBTU | 50,000 |
Contract price | $ / MMBTU | 3.065 |
Oil Costless Collars [Member] | Derivative Contract Period Ten [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Costless Collars [Member] | Derivative Contract Period Ten [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | 47.50 |
Oil Costless Collars [Member] | Derivative Contract Period Ten [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | 52.50 |
Oil Costless Collars [Member] | Derivative Contract Period Eleven [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Costless Collars [Member] | Derivative Contract Period Eleven [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | 48 |
Oil Costless Collars [Member] | Derivative Contract Period Eleven [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | 53.25 |
Oil Costless Collars [Member] | Derivative Contract Period Twelve [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Costless Collars [Member] | Derivative Contract Period Twelve [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | 50 |
Oil Costless Collars [Member] | Derivative Contract Period Twelve [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | 55.75 |
Oil Costless Collars [Member] | Derivative Contract Period Thirteen [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Oil | bbl | 3,000 |
Oil Costless Collars [Member] | Derivative Contract Period Thirteen [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | 50 |
Oil Costless Collars [Member] | Derivative Contract Period Thirteen [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | 58 |
Oil Costless Collars [Member] | Derivative Contract Period Fourteen [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Costless Collars [Member] | Derivative Contract Period Fourteen [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | 55 |
Oil Costless Collars [Member] | Derivative Contract Period Fourteen [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | 63.45 |
Oil Costless Collars [Member] | Derivative Contract Period Fifteen [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Oil | bbl | 1,000 |
Oil Costless Collars [Member] | Derivative Contract Period Fifteen [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | 50 |
Oil Costless Collars [Member] | Derivative Contract Period Fifteen [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | 60 |
Oil Costless Collars [Member] | Derivative Contract Period Sixteen [Member] | |
Derivative [Line Items] | |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Costless Collars [Member] | Derivative Contract Period Sixteen [Member] | Minimum [Member] | |
Derivative [Line Items] | |
Contract price | 60 |
Oil Costless Collars [Member] | Derivative Contract Period Sixteen [Member] | Maximum [Member] | |
Derivative [Line Items] | |
Contract price | 69.25 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Seventeen [Member] | |
Derivative [Line Items] | |
Contract price | 50.72 |
Production volume covered per month - Oil | bbl | 3,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Eighteen [Member] | |
Derivative [Line Items] | |
Contract price | 52.02 |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Nineteen [Member] | |
Derivative [Line Items] | |
Contract price | 54.14 |
Production volume covered per month - Oil | bbl | 4,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Twenty [Member] | |
Derivative [Line Items] | |
Contract price | 58.20 |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Twenty One [Member] | |
Derivative [Line Items] | |
Contract price | 59.69 |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Twenty Two [Member] | |
Derivative [Line Items] | |
Contract price | 57.15 |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Twenty Three [Member] | |
Derivative [Line Items] | |
Contract price | 58.02 |
Production volume covered per month - Oil | bbl | 3,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Twenty Four [Member] | |
Derivative [Line Items] | |
Contract price | 56.15 |
Production volume covered per month - Oil | bbl | 1,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Twenty Five [Member] | |
Derivative [Line Items] | |
Contract price | 56.71 |
Production volume covered per month - Oil | bbl | 2,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Twenty Six [Member] | |
Derivative [Line Items] | |
Contract price | 58.56 |
Production volume covered per month - Oil | bbl | 1,000 |
Oil Fixed Price Swaps [Member] | Derivative Contract Period Twenty Seven [Member] | |
Derivative [Line Items] | |
Contract price | 56.85 |
Production volume covered per month - Oil | bbl | 2,000 |