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Derivative Financial Instruments (Details) | Feb. 17, 2016 MMBTU $ / EnergyContent $ / Barrels bbl | Jan. 14, 2016 MMBTU $ / EnergyContent | Dec. 31, 2015 MMBTU $ / EnergyContent $ / Barrels bbl
--- | --- | --- | ---
NYMEX Oil Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 5,600,000
Gas Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 172,700,000
NGL Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 13,000,000
NYMEX Oil Swap Contract First Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,868,000
Weighted- Average Contract Price | $ / Barrels |  |  | 86.93
NYMEX Oil Swap Contract Second Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,752,000
Weighted- Average Contract Price | $ / Barrels |  |  | 86.73
NYMEX Oil Swap Contract Third Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,170,000
Weighted- Average Contract Price | $ / Barrels |  |  | 90.29
NYMEX Oil Swap Contract Fourth Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 780,000
Weighted- Average Contract Price | $ / Barrels |  |  | 90.05
NYMEX Oil Swap Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 5,570,000
Gas Swaps Contract First Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent |  |  | 3.82
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 23,341,000
Gas Swaps Contract Second Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent |  |  | 3.40
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 20,780,000
Gas Swaps Contract Third Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent |  |  | 3.38
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 18,829,000
Gas Swaps Contract Fourth Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent |  |  | 3.82
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 17,236,000
Gas Swaps Contract 2017 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent |  |  | 4.09
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 37,528,000
Gas Swaps Contract 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent |  |  | 4.27
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 30,606,000
Gas Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent |  |  | 4.34
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 24,415,000
Gas Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU |  |  | 172,735,000
IF El Paso Permian [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 2.00%
IF NNG Ventura [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 2.00%
IF NGPL TXOK [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 1.00%
IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 95.00%
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract First Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 926,000
Weighted- Average Contract Price | $ / Barrels |  |  | 8.29
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract Second Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 828,000
Weighted- Average Contract Price | $ / Barrels |  |  | 8.28
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract Third Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 751,000
Weighted- Average Contract Price | $ / Barrels |  |  | 8.70
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract Fourth Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 688,000
Weighted- Average Contract Price | $ / Barrels |  |  | 8.71
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract 2017 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 2,271,000
Weighted- Average Contract Price | $ / Barrels |  |  | 9.16
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,671,000
Weighted- Average Contract Price | $ / Barrels |  |  | 10.65
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,200,000
Weighted- Average Contract Price | $ / Barrels |  |  | 10.92
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 539,000
Weighted- Average Contract Price | $ / Barrels |  |  | 11.13
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 8,874,000
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,059,000
Weighted- Average Contract Price | $ / Barrels |  |  | 19.60
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 949,000
Weighted- Average Contract Price | $ / Barrels |  |  | 19.64
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 862,000
Weighted- Average Contract Price | $ / Barrels |  |  | 19.03
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 791,000
Weighted- Average Contract Price | $ / Barrels |  |  | 18.53
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2017 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,661,000
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 143,000
Weighted- Average Contract Price | $ / Barrels |  |  | 25.62
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 130,000
Weighted- Average Contract Price | $ / Barrels |  |  | 25.62
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2017 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 273,000
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 122,000
Weighted- Average Contract Price | $ / Barrels |  |  | 25.87
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 111,000
Weighted- Average Contract Price | $ / Barrels |  |  | 25.87
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2017 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Weighted- Average Contract Price | $ / Barrels |  |  | 0.00
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 233,000
Subsequent Event [Member] | Gas Swaps Contract First Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent | 3.82 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | 23,341,000 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | 0 |
Derivative, Swap Type, Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 0.00 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes | MMBTU | 23,341,000 |  |
Subsequent Event [Member] | Gas Swaps Contract Second Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent | 3.40 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | 20,780,000 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | 0 |
Derivative, Swap Type, Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 0.00 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes | MMBTU | 20,780,000 |  |
Subsequent Event [Member] | Gas Swaps Contract Third Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent | 3.38 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | 18,829,000 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | 0 |
Derivative, Swap Type, Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 0.00 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes | MMBTU | 18,829,000 |  |
Subsequent Event [Member] | Gas Swaps Contract Fourth Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent | 3.82 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | 17,236,000 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | 0 |
Derivative, Swap Type, Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 0.00 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes | MMBTU | 17,236,000 |  |
Subsequent Event [Member] | Gas Swaps Contract 2017 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent | 4.26 | 4.43 |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | 76,135,000 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Sold Volumes on Subsequent Date | MMBTU |  | 38,600,000 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | 0 |
Derivative, Swap Type, Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 0.00 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes | MMBTU | 76,135,000 |  |
Subsequent Event [Member] | Gas Swaps Contract 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent | 4.27 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | 30,606,000 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | (30,606,000) |
Derivative, Swap Type, Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 4.27 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes | MMBTU | 0 |  |
Subsequent Event [Member] | Gas Swaps Contract 2019 [Member] |  |  |
Derivative Financial Instruments |  |  |
Weighted- Average Contract Price | $ / EnergyContent | 4.34 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | 24,415,000 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | (24,415,000) |
Derivative, Swap Type, Average Fixed Price, Purchased Volumes | $ / EnergyContent |  | 4.34 |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes | MMBTU | 0 |  |
Subsequent Event [Member] | Gas Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | 211,342,000 |  |
Derivative, Nonmonetary Notional Amount, Energy Measure, Purchased Volumes | MMBTU |  | (55,021,000) |
Derivative, Nonmonetary Notional Amount, Energy Measure, Net of Purchased Volumes | MMBTU | 156,321,000 |  |
Subsequent Event [Member] | IF El Paso Permian [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps | 2.00% |  |
Subsequent Event [Member] | IF NNG Ventura [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps | 1.00% |  |
Subsequent Event [Member] | IF NGPL TXOK [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps | 1.00% |  |
Subsequent Event [Member] | IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps | 96.00% |  |
Subsequent Event [Member] | OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract 2018 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume | 1,600,000 |  |
Weighted- Average Contract Price | $ / Barrels | 8.67 |  |
Subsequent Event [Member] | OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter 2016 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume | 235,000 |  |
Weighted- Average Contract Price | $ / Barrels | 22.58 |  |

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