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Derivative Financial Instruments (Details) bbl in Thousands, BTU in Billions | Feb. 17, 2021 BTU $ / Barrels $ / EnergyContent bbl | Dec. 31, 2020 BTU $ / Barrels $ / EnergyContent bbl
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NYMEX Oil Swap Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,613
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 42.91
NYMEX Oil Swap Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 5,072
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 39.90
NYMEX Oil Swap Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 4,862
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 40.10
NYMEX Oil Swap Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 4,744
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 39.85
NYMEX Oil Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 6,601
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 43.99
NYMEX Oil Swap Contract, 2023 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,190
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 45.20
NYMEX Oil Swap Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 26,082
NYMEX Oil Collar Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 551
Derivative, Floor Price | $ / Barrels |  | 48.97
Derivative, Ceiling Price | $ / Barrels |  | 51.96
NYMEX Oil Collar Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 551
NYMEX Oil Roll Differential Swap Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,367
Derivative, Oil Roll Differential Swap, Weighted-Average Contract Price | $ / Barrels |  | (0.30)
NYMEX Oil Roll Differential Swap Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 4,065
Derivative, Oil Roll Differential Swap, Weighted-Average Contract Price | $ / Barrels |  | (0.24)
NYMEX Oil Roll Differential Swap Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,708
Derivative, Oil Roll Differential Swap, Weighted-Average Contract Price | $ / Barrels |  | (0.25)
NYMEX Oil Roll Differential Swap Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,283
Derivative, Oil Roll Differential Swap, Weighted-Average Contract Price | $ / Barrels |  | (0.24)
NYMEX Oil Roll Differential Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 6,002
Derivative, Oil Roll Differential Swap, Weighted-Average Contract Price | $ / Barrels |  | (0.04)
NYMEX Oil Roll Differential Swap Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 20,425
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,223
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | 0.79
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,385
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | 0.78
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 3,574
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | 0.74
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, 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, Weighted-Average Contract Price | $ / Barrels |  | 1.15
WTI Midland NYMEX WTI [Member] | Oil Basis Swap [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 23,506
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 900
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | (7.86)
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, 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, 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, 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, Weighted-Average Contract Price | $ / Barrels |  | (7.78)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 7,300
WTI Houston MEH NYMEX WTI [Member] | Oil Basis Swap Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 173
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | 0.60
WTI Houston MEH NYMEX WTI [Member] | Oil Basis Swap Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 493
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | 0.60
WTI Houston MEH NYMEX WTI [Member] | Oil Basis Swap Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 356
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | 0.60
WTI Houston MEH NYMEX WTI [Member] | Oil Basis Swap Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 466
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | 0.60
WTI Houston MEH NYMEX WTI [Member] | Oil Basis Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 0
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels |  | 0
WTI Houston MEH NYMEX WTI [Member] | Oil Basis Swap [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,488
IF HSC [Member] | Gas Swaps Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 11,592
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 2.48
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, Average Fixed 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, Average Fixed 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, Average Fixed Price | $ / EnergyContent |  | 2.41
IF HSC [Member] | Gas Swaps Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 21,119
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 2.48
IF HSC [Member] | Gas Swaps Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 71,370
WAHA [Member] | Gas Swaps Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 6,544
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 1.76
WAHA [Member] | Gas Swaps Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 7,230
Derivative, Swap Type, Average Fixed 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, Average Fixed 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, Average Fixed Price | $ / EnergyContent |  | 1.82
WAHA [Member] | Gas Swaps Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 10,066
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  | 2.30
WAHA [Member] | Gas Swaps Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  | 39,553
IF WAHA [Member] |  |
Derivative Financial Instruments |  |
Index percent of natural gas fixed swaps |  | 59.00%
GD Waha [Member] |  |
Derivative Financial Instruments |  |
Index percent of natural gas fixed swaps |  | 41.00%
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 614
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 21.58
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 707
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 21.26
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 735
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 21.26
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 714
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 21.30
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 116
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 21.21
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 2,886
Subsequent Event [Member] | NYMEX Oil Swap Contract, First Quarter to Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 1,048 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels | 51.91 |
Subsequent Event [Member] | NYMEX Oil Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 1,222 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels | 48.50 |
Subsequent Event [Member] | NYMEX Oil Collar Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 1,095 |
Derivative, Floor Price | $ / Barrels | 50.00 |
Derivative, Ceiling Price | $ / Barrels | 53.28 |
Subsequent Event [Member] | NYMEX Oil Roll Differential Swap Contract, First Quarter to Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 2,213 |
Derivative, Oil Roll Differential Swap, Weighted-Average Contract Price | $ / Barrels | 0.30 |
Subsequent Event [Member] | NYMEX Oil Roll Differential Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 5,276 |
Derivative, Oil Roll Differential Swap, Weighted-Average Contract Price | $ / Barrels | 0.27 |
Subsequent Event [Member] | WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract, First Quarter to Third Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 1,095 |
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels | 0.95 |
Subsequent Event [Member] | WTI Houston MEH NYMEX WTI [Member] | Oil Basis Swap Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 1,329 |
Derivative, Oil Basis Swap, Weighted-Average Contract Price | $ / Barrels | 1.25 |
Subsequent Event [Member] | IF HSC [Member] | Gas Swaps Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU | 7,813 |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent | 2.64 |
Subsequent Event [Member] | IF WAHA [Member] | Gas Swaps Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU | 3,650 |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent | 2.30 |
Subsequent Event [Member] | OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter to Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 440 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels | 27.72 |
Subsequent Event [Member] | OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 115 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels | 24.78 |
Subsequent Event [Member] | OPIS Propane Mont Belvieu Non-TET [Member] | NGL Collar Contract, 2022 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 234 |
Derivative, Floor Price | $ / Barrels | 22.05 |
Derivative, Ceiling Price | $ / Barrels | 27.30 |
Subsequent Event [Member] | OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract First Quarter to Fourth Quarter, 2021 [Member] |  |
Derivative Financial Instruments |  |
Derivative, Nonmonetary Notional Amount, Volume | 143 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels | 30.87 |

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