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Derivative Financial Instruments (Details) bbl in Thousands, BTU in Billions | Feb. 19, 2020 $ / Barrels bbl | Dec. 31, 2019 BTU $ / EnergyContent $ / Barrels bbl
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IF WAHA [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 92.00%
GD Waha [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 8.00%
Subsequent Event [Member] | WTI Midland NYMEX WTI [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 16,300 |
Derivative, Weighted-Average Contract Price | $ / Barrels |  | 1.14 |
NYMEX Oil Swap Contract First Quarter, 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 2,486
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 59.65
NYMEX Oil Swap Contract Second Quarter, 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 2,838
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 58.81
NYMEX Oil Swap Contract Third Quarter, 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,361
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 56.43
NYMEX Oil Swap Contract Fourth Quarter, 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,937
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 56.94
NYMEX Oil Swap Contract, 2021 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 667
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 56.00
NYMEX Oil Swap Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 13,289
NYMEX Oil Swap Contracts [Member] | Subsequent Event [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 600 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 57.82 |
NYMEX Oil Collar Contract First Quarter, 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 2,267
Derivative, Floor Price | $ / Barrels |  |  | 55.00
Derivative, Ceiling Price | $ / Barrels |  |  | 63.91
NYMEX Oil Collar Contract Second Quarter, 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,881
Derivative, Floor Price | $ / Barrels |  |  | 55.00
Derivative, Ceiling Price | $ / Barrels |  |  | 62.17
NYMEX Oil Collar Contract Third Quarter, 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,252
Derivative, Floor Price | $ / Barrels |  |  | 55.00
Derivative, Ceiling Price | $ / Barrels |  |  | 62.90
NYMEX Oil Collar Contract Fourth Quarter, 2020 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 610
Derivative, Floor Price | $ / Barrels |  |  | 55.00
Derivative, Ceiling Price | $ / Barrels |  |  | 61.90
NYMEX Oil Collar Contract, 2021 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 329
Derivative, Floor Price | $ / Barrels |  |  | 55.00
Derivative, Ceiling Price | $ / Barrels |  |  | 56.70
NYMEX Oil Collar Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 6,339
Oil Basis Swap Contract First Quarter, 2020 [Member] | WTI Midland NYMEX WTI [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 4,193
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | (0.68)
Oil Basis Swap Contract First Quarter, 2020 [Member] | NYMEX WTI ICE Brent [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | 0
Oil Basis Swap Contract Second Quarter, 2020 [Member] | WTI Midland NYMEX WTI [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,495
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | (0.68)
Oil Basis Swap Contract Second Quarter, 2020 [Member] | NYMEX WTI ICE Brent [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 910
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | (8.06)
Oil Basis Swap Contract Third Quarter, 2020 [Member] | WTI Midland NYMEX WTI [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,325
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | (0.74)
Oil Basis Swap Contract Third Quarter, 2020 [Member] | NYMEX WTI ICE Brent [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 920
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | (8.01)
Oil Basis Swap Contract Fourth Quarter, 2020 [Member] | WTI Midland NYMEX WTI [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,261
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | (0.73)
Oil Basis Swap Contract Fourth Quarter, 2020 [Member] | NYMEX WTI ICE Brent [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 920
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | (8.01)
Oil Basis Swap Contract, 2021 [Member] | WTI Midland NYMEX WTI [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 5,954
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | 0.59
Oil Basis Swap Contract, 2021 [Member] | NYMEX WTI ICE Brent [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,650
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | (7.86)
Oil Basis Swap Contract, 2022 [Member] | WTI Midland NYMEX WTI [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | 0
Oil Basis Swap Contract, 2022 [Member] | NYMEX WTI ICE Brent [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,650
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | (7.78)
Oil Basis Swap [Member] | WTI Midland NYMEX WTI [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 20,228
Oil Basis Swap [Member] | NYMEX WTI ICE Brent [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 10,050
Gas Swaps Contract First Quarter, 2020 [Member] | IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 9,123
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.98
Gas Swaps Contract First Quarter, 2020 [Member] | WAHA [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 3,099
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 1.93
Gas Swaps Contract Second Quarter, 2020 [Member] | IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 4,160
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.20
Gas Swaps Contract Second Quarter, 2020 [Member] | WAHA [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 3,196
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 0.56
Gas Swaps Contract Third Quarter, 2020 [Member] | IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 4,493
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.41
Gas Swaps Contract Third Quarter, 2020 [Member] | WAHA [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 3,268
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 1.03
Gas Swaps Contract Fourth Quarter, 2020 [Member] | IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 3,722
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.36
Gas Swaps Contract Fourth Quarter, 2020 [Member] | WAHA [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 3,419
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 1.17
Gas Swaps Contract, 2021 [Member] | IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 0
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 0
Gas Swaps Contract, 2021 [Member] | WAHA [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 4,224
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 1.51
Gas Swaps Contracts [Member] | IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU | [3] |  | 21,498
Gas Swaps Contracts [Member] | WAHA [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU | [3] |  | 17,206
NGL Swaps Contract First Quarter, 2020 [Member] | OPIS Purity Ethane Mont Belvieu [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 447
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 11.53
NGL Swaps Contract First Quarter, 2020 [Member] | OPIS Propane Mont Belvieu Non-TET [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 382
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 22.64
NGL Swaps Contract Second Quarter, 2020 [Member] | OPIS Purity Ethane Mont Belvieu [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 264
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 11.13
NGL Swaps Contract Second Quarter, 2020 [Member] | OPIS Propane Mont Belvieu Non-TET [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 382
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 22.34
NGL Swaps Contract Third Quarter, 2020 [Member] | OPIS Purity Ethane Mont Belvieu [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 0
NGL Swaps Contract Third Quarter, 2020 [Member] | OPIS Propane Mont Belvieu Non-TET [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 409
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 22.33
NGL Swaps Contract Fourth Quarter, 2020 [Member] | OPIS Purity Ethane Mont Belvieu [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 0
NGL Swaps Contract Fourth Quarter, 2020 [Member] | OPIS Propane Mont Belvieu Non-TET [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 466
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 22.29
NGL Swaps Contracts [Member] | OPIS Purity Ethane Mont Belvieu [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 711
NGL Swaps Contracts [Member] | OPIS Propane Mont Belvieu Non-TET [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,639
[1] | (1) Represents the price differential between WTI Midland (Midland, Texas) and NYMEX WTI (Cushing, Oklahoma).
[2] | (2) Represents the price differential between NYMEX WTI (Cushing, Oklahoma) and ICE Brent (North Sea).
[3] | (1) The Company has natural gas swaps in place that settle against Inside FERC Houston Ship Channel (“IF HSC”), Inside FERC West Texas (“IF WAHA”), and Platt’s Gas Daily West Texas (“GD WAHA”). As of December 31, 2019, WAHA volumes were comprised of 92 percent IF WAHA and eight percent GD WAHA

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