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Derivative Financial Instruments (Details) bbl in Thousands, MMBTU in Thousands |  | 2 Months Ended
--- | --- | ---
Dec. 31, 2017 MMBTU $ / EnergyContent $ / Barrels bbl | Feb. 14, 2018 $ / Barrels bbl
NYMEX Oil Swap Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,075 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 50.16 |
NYMEX Oil Swap Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,534 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 49.57 |
NYMEX Oil Swap Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,769 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 49.77 |
NYMEX Oil Swap Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,894 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 49.87 |
NYMEX Oil Swap Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,940 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 50.70 |
NYMEX Oil Swap Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 8,212 |
NYMEX Oil Collar Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,445 |
Derivative, Floor Price | $ / Barrels |  | 50.00 |
Derivative, Ceiling Price | $ / Barrels |  | 59.07 |
NYMEX Oil Collar Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,459 |
Derivative, Floor Price | $ / Barrels |  | 50.00 |
Derivative, Ceiling Price | $ / Barrels |  | 59.03 |
NYMEX Oil Collar Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,948 |
Derivative, Floor Price | $ / Barrels |  | 50.00 |
Derivative, Ceiling Price | $ / Barrels |  | 58.61 |
NYMEX Oil Collar Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 2,222 |
Derivative, Floor Price | $ / Barrels |  | 50.00 |
Derivative, Ceiling Price | $ / Barrels |  | 58.44 |
NYMEX Oil Collar Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 5,908 |
Derivative, Floor Price | $ / Barrels |  | 47.65 |
Derivative, Ceiling Price | $ / Barrels |  | 59.19 |
NYMEX Oil Collar Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 12,982 |
Oil Basis Swap Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 2,113 |
Weighted-Average Contract Price | $ / Barrels | [1] | (1.15) |
Oil Basis Swap Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 2,392 |
Weighted-Average Contract Price | $ / Barrels | [1] | (1.03) |
Oil Basis Swap Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,018 |
Weighted-Average Contract Price | $ / Barrels | [1] | (1.06) |
Oil Basis Swap Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,327 |
Weighted-Average Contract Price | $ / Barrels | [1] | (1.08) |
Oil Basis Swap Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 5,788 |
Weighted-Average Contract Price | $ / Barrels | [1] | (1.09) |
Oil Basis Swap [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 16,638 |
Gas Swaps Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 3.55 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Sold Volumes | MMBTU |  | 28,910 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | (8,121) |
Derivative, Swap Type, Weighted-Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 4.34 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net Volumes | MMBTU | [2] | 20,789 |
Gas Swaps Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 3.31 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Sold Volumes | MMBTU |  | 23,507 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | (7,795) |
Derivative, Swap Type, Weighted-Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 4.24 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net Volumes | MMBTU | [2] | 15,712 |
Gas Swaps Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 3.29 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Sold Volumes | MMBTU |  | 24,627 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | (7,480) |
Derivative, Swap Type, Weighted-Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 4.23 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net Volumes | MMBTU | [2] | 17,147 |
Gas Swaps Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 3.29 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Sold Volumes | MMBTU |  | 25,856 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | (7,210) |
Derivative, Swap Type, Weighted-Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 4.27 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net Volumes | MMBTU | [2] | 18,646 |
Gas Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 3.76 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Sold Volumes | MMBTU |  | 41,394 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | (24,415) |
Derivative, Swap Type, Weighted-Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 4.34 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net Volumes | MMBTU | [2] | 16,979 |
Gas Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Sold Volumes | MMBTU | [2] | 144,294 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU | [2] | (55,021) |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net Volumes | MMBTU | [2] | 89,273 |
IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  | 99.00% |
IF El Paso Permian [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  | 1.00% |
OPIS Purity Ethane Mont Belvieu [Member] | NGL Swaps Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 923 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 10.90 |
OPIS Purity Ethane Mont Belvieu [Member] | NGL Swaps Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 915 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 10.87 |
OPIS Purity Ethane Mont Belvieu [Member] | NGL Swaps Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,033 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 10.99 |
OPIS Purity Ethane Mont Belvieu [Member] | NGL Swaps Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,146 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 11.18 |
OPIS Purity Ethane Mont Belvieu [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,533 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 12.31 |
OPIS Purity Ethane Mont Belvieu [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 539 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 11.13 |
OPIS Purity Ethane Mont Belvieu [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 8,089 |
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 629 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 25.39 |
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 554 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 24.94 |
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 610 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 24.27 |
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 671 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 24.39 |
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,503 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 27.83 |
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 0 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 0 |
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,967 |
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 206 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.83 |
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 84 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.69 |
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 93 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.70 |
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 102 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.70 |
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 154 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.64 |
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 0 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 0 |
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 639 |
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 167 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.76 |
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 66 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.07 |
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 70 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.07 |
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 76 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.07 |
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 117 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 35.70 |
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 0 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 0 |
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 496 |
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 188 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 49.40 |
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 109 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 49.57 |
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 118 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 49.56 |
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 129 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 49.57 |
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 197 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 50.93 |
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 0 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 0 |
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 741 |
Subsequent Event [Member] | OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 228
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 53.34
[1] | Represents the price differential between WTI prices at Midland, Texas and WTI prices at Cushing, Oklahoma.
[2] | Total net volumes of gas swaps are comprised of IF HSC (99%) and IF El Paso Permian (1%).

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- Definition Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes + References No definition available. + Details
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