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Derivative Financial Instruments (Details) bbl in Thousands, BTU in Billions | Apr. 29, 2021 $ / Barrels bbl | Mar. 31, 2021 BTU $ / Barrels $ / EnergyContent bbl
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NYMEX Oil Swap Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 5,508
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 40.88
NYMEX Oil Swap Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 5,363
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 41.16
NYMEX Oil Swap Contract Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 4,744
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 39.85
NYMEX Oil Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 7,823
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 44.69
NYMEX Oil Swap Contract, 2023 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,190
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 45.20
NYMEX Oil Swap Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 24,628
NYMEX Oil Collar Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,224
Derivative, Weighted-Average Floor Price | $ / Barrels |  | 50.00
Derivative, Weighted-Average Ceiling Price | $ / Barrels |  | 54.89
NYMEX Oil Calendar Month Average Roll Differential Second Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 4,743
Derivative, Roll Differential Swap Type, Weighted-Average Contract Price | $ / Barrels |  | (0.16)
NYMEX Oil Calendar Month Average Roll Differential Contract Third Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 4,326
Derivative, Roll Differential Swap Type, Weighted-Average Contract Price | $ / Barrels |  | (0.18)
NYMEX Oil Calendar Month Average Roll Differential Fourth Quarter, 2021 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,831
Derivative, Roll Differential Swap Type, Weighted-Average Contract Price | $ / Barrels |  | (0.16)
NYMEX Oil Calendar Month Average Roll Differential Contract, 2022 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 11,278
Derivative, Roll Differential Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 0.11
NYMEX Oil Calendar Month Average Roll Differential Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 24,178
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 4,172
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 0.81
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,756
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 0.75
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,824
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 0.71
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 9,500
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 1.15
WTI Midland NYMEX WTI [Member] | Oil Basis Swap [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 21,252
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 910
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | (7.86)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 920
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | (7.86)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 920
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | (7.86)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,650
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | (7.78)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 6,400
WTI Houston MEH NYMEX WTI | Oil Basis Swap Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 493
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 0.60
WTI Houston MEH NYMEX WTI | Oil Basis Swap Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 356
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 0.60
WTI Houston MEH NYMEX WTI | Oil Basis Swap Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 466
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 0.60
WTI Houston MEH NYMEX WTI | Oil Basis Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,329
Derivative, Oil Basis Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 1.25
WTI Houston MEH NYMEX WTI | Oil Basis Swap [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 2,644
IF HSC [Member] | Gas Swaps Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 13,672
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 2.45
IF HSC [Member] | Gas Swaps Contract Third Quarter, 2021 [Member] |  |
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 [Member] |  |
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 [Member] |  |
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 Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 67,591
WAHA [Member] | Gas Swaps Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 7,230
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 1.76
WAHA [Member] | Gas Swaps Contract Third Quarter, 2021 [Member] |  |
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 [Member] |  |
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 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 13,716
Derivative, Swap Type, Weighted-Average Contract Price | $ / EnergyContent |  | 2.30
WAHA [Member] | Gas Swaps Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 36,659
IF WAHA [Member] |  |
Derivative Financial Instruments |  |
Index percent of natural gas fixed swaps |  | 65.00%
GD WAHA [Member] |  |
Derivative Financial Instruments |  |
Index percent of natural gas fixed swaps |  | 35.00%
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 818
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 22.14
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 854
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 22.16
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 824
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 22.15
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 231
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 22.99
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 2,727
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Collar Contract, Year 2 |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 234
Derivative, Weighted-Average Floor Price | $ / Barrels |  | 22.05
Derivative, Weighted-Average Ceiling Price | $ / Barrels |  | 27.30
OPIS Normal Butane Mont Belvieu | NGL Swaps Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 37
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 30.87
OPIS Normal Butane Mont Belvieu | NGL Swaps Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 37
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 30.87
OPIS Normal Butane Mont Belvieu | NGL Swaps Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 36
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 30.87
OPIS Normal Butane Mont Belvieu | NGL Swaps Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 0
Derivative, Swap Type, Weighted-Average Contract Price | $ / Barrels |  | 0
OPIS Normal Butane Mont Belvieu | NGL Swaps Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 110
Subsequent Event [Member] | NYMEX Oil Collar Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 180 |
Derivative, Weighted-Average Floor Price | $ / Barrels | 50.00 |
Derivative, Weighted-Average Ceiling Price | $ / Barrels | 65.00 |

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