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Derivative Financial Instruments (Details) bbl in Thousands, BTU in Billions | Jul. 29, 2021 $ / Barrels bbl | Jun. 30, 2021 BTU $ / Barrels $ / EnergyContent bbl
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NYMEX Oil Swap Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 5,363
Derivative, Swap Type, Weighted-Average Contract Price |  | 41.16
NYMEX Oil Swap Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 4,744
Derivative, Swap Type, Weighted-Average Contract Price |  | 39.85
NYMEX Oil Swap Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 7,823
Derivative, Swap Type, Weighted-Average Contract Price |  | 44.69
NYMEX Oil Swap Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 1,190
Derivative, Swap Type, Weighted-Average Contract Price |  | 45.20
NYMEX Oil Collar Contract, Third Quarter 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Weighted-Average Floor Price |  | 0
Derivative, Weighted-Average Ceiling Price |  | 0
NYMEX Oil Collar Contract, Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Weighted-Average Floor Price |  | 0
Derivative, Weighted-Average Ceiling Price |  | 0
NYMEX Oil Collar Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 1,721
Derivative, Weighted-Average Floor Price |  | 51.84
Derivative, Weighted-Average Ceiling Price |  | 58.37
NYMEX Oil Collar Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Weighted-Average Floor Price |  | 0
Derivative, Weighted-Average Ceiling Price |  | 0
NYMEX Oil Calendar Month Average Roll Differential Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 4,326
Derivative, Roll Differential Swap Type, Weighted-Average Contract Price |  | (0.18)
NYMEX Oil Calendar Month Average Roll Differential Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 3,831
Derivative, Roll Differential Swap Type, Weighted-Average Contract Price |  | (0.16)
NYMEX Oil Calendar Month Average Roll Differential Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 11,278
Derivative, Roll Differential Swap Type, Weighted-Average Contract Price |  | 0.11
NYMEX Oil Calendar Month Average Roll Differential Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 1,832
Derivative, Roll Differential Swap Type, Weighted-Average Contract Price |  | 0.39
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 3,756
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 0.75
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 3,824
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 0.71
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 9,500
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 1.15
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 0
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 920
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | (7.86)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 920
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | (7.86)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 3,650
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | (7.78)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 0
WTI Houston MEH NYMEX WTI | Oil Basis Swap Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 356
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 0.60
WTI Houston MEH NYMEX WTI | Oil Basis Swap Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 466
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 0.60
WTI Houston MEH NYMEX WTI | Oil Basis Swap Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 1,329
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 1.25
WTI Houston MEH NYMEX WTI | Oil Basis Swap Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price |  | 0
IF HSC [Member] | Gas Swaps Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 12,575
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 2.40
IF HSC [Member] | Gas Swaps Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 12,412
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 2.41
IF HSC [Member] | Gas Swaps Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 28,932
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 2.52
IF HSC [Member] | Gas Swaps Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 0
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 0
WAHA [Member] | Gas Swaps Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 8,086
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 1.88
WAHA [Member] | Gas Swaps Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 7,627
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 1.82
WAHA [Member] | Gas Swaps Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 14,087
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 2.32
WAHA [Member] | Gas Swaps Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 0
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 0
IF Tenn TX Z0 | Gas Swaps Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 0
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 0
IF Tenn TX Z0 | Gas Swaps Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 0
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 0
IF Tenn TX Z0 | Gas Swaps Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 513
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 3.22
IF Tenn TX Z0 | Gas Swaps Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 0
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 0
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 854
Derivative, Swap Type, Weighted-Average Contract Price |  | 22.16
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 824
Derivative, Swap Type, Weighted-Average Contract Price |  | 22.15
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 461
Derivative, Swap Type, Weighted-Average Contract Price |  | 27.19
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Swap Type, Weighted-Average Contract Price |  | 0
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Collar Contract, Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Weighted-Average Floor Price |  | 0
Derivative, Weighted-Average Ceiling Price |  | 0
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Collar Contract, Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Weighted-Average Floor Price |  | 0
Derivative, Weighted-Average Ceiling Price |  | 0
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Collar Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 627
Derivative, Weighted-Average Floor Price |  | 23.83
Derivative, Weighted-Average Ceiling Price |  | 29.19
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Collar Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Weighted-Average Floor Price |  | 0
Derivative, Weighted-Average Ceiling Price |  | 0
OPIS Normal Butane Mont Belvieu | NGL Swaps Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 37
Derivative, Swap Type, Weighted-Average Contract Price |  | 30.87
OPIS Normal Butane Mont Belvieu | NGL Swaps Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 36
Derivative, Swap Type, Weighted-Average Contract Price |  | 30.87
OPIS Normal Butane Mont Belvieu | NGL Swaps Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Swap Type, Weighted-Average Contract Price |  | 0
OPIS Normal Butane Mont Belvieu | NGL Swaps Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl |  | 0
Derivative, Swap Type, Weighted-Average Contract Price |  | 0
IF WAHA [Member] |  |
Derivative Financial Instruments |  |
Index percent of natural gas fixed swaps |  | 70.00%
GD WAHA [Member] |  |
Derivative Financial Instruments |  |
Index percent of natural gas fixed swaps |  | 30.00%
Subsequent Event [Member] | NYMEX Oil Swap Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl | 400 |
Derivative, Swap Type, Weighted-Average Contract Price | 70.09 |
Subsequent Event [Member] | OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | bbl | 100 |
Derivative, Swap Type, Weighted-Average Contract Price | 35.70 |

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