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Derivative Financial Instruments (Details) bbl in Thousands, BTU in Billions | May 02, 2019 $ / Barrels bbl | Mar. 31, 2019 BTU $ / EnergyContent $ / Barrels bbl
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NYMEX Oil Swap Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 575
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 55.52
NYMEX Oil Swap Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,217
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 61.41
NYMEX Oil Swap Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,115
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 59.97
NYMEX Oil Swap Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 2,491
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 65.68
NYMEX Oil Swap Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 5,398
NYMEX Oil Collar Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,034
Derivative, Weighted- Average Floor Price | $ / Barrels |  |  | 52.39
Derivative, Weighted-Average Ceiling Price | $ / Barrels |  |  | 64.32
NYMEX Oil Collar Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 2,547
Derivative, Weighted- Average Floor Price | $ / Barrels |  |  | 49.50
Derivative, Weighted-Average Ceiling Price | $ / Barrels |  |  | 62.64
NYMEX Oil Collar Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,168
Derivative, Weighted- Average Floor Price | $ / Barrels |  |  | 50.54
Derivative, Weighted-Average Ceiling Price | $ / Barrels |  |  | 62.49
NYMEX Oil Collar Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,405
Derivative, Weighted- Average Floor Price | $ / Barrels |  |  | 55.00
Derivative, Weighted-Average Ceiling Price | $ / Barrels |  |  | 63.00
NYMEX Oil Collar Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 12,154
Gas Collar Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 14,242
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 2,571
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | (4.49)
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,291
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | (2.86)
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,338
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | (2.87)
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 11,601
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | (1.03)
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract, Year 3 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,707
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | 0.33
WTI Midland NYMEX WTI [Member] | Oil Basis Swap Contract, Year 4 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Weighted-Average Contract Price | $ / Barrels | [1] |  | 0.00
WTI Midland NYMEX WTI [Member] | Oil Basis Swap [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 24,508
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | 0.00
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | 0.00
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | 0.00
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 2,750
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | (8.03)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract, Year 3 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,650
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | (7.86)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap Contract, Year 4 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,650
Derivative, Weighted-Average Contract Price | $ / Barrels | [2] |  | (7.78)
NYMEX WTI ICE Brent [Member] | Oil Basis Swap [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 10,050
IF HSC [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 78.00%
IF HSC [Member] | Gas Swaps Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.82
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 11,177
IF HSC [Member] | Gas Swaps Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.84
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 14,102
IF HSC [Member] | Gas Swaps Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.88
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 14,433
IF HSC [Member] | Gas Swaps Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.98
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 9,123
IF HSC [Member] | Gas Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU | [3] |  | 48,835
IF HSC [Member] | Gas Collar Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Weighted- Average Floor Price | $ / EnergyContent |  |  | 2.50
Derivative, Weighted-Average Ceiling Price | $ / EnergyContent |  |  | 2.83
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 4,358
IF HSC [Member] | Gas Collar Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Weighted- Average Floor Price | $ / EnergyContent |  |  | 2.50
Derivative, Weighted-Average Ceiling Price | $ / EnergyContent |  |  | 2.83
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 5,066
IF HSC [Member] | Gas Collar Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Weighted- Average Floor Price | $ / EnergyContent |  |  | 2.50
Derivative, Weighted-Average Ceiling Price | $ / EnergyContent |  |  | 2.83
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 4,818
WAHA [Member] | Gas Swaps Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 0.70
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 4,546
WAHA [Member] | Gas Swaps Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 1.30
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 4,340
WAHA [Member] | Gas Swaps Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 1.75
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 2,962
WAHA [Member] | Gas Swaps Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Swap Type, Average Fixed Price | $ / EnergyContent |  |  | 2.20
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU |  |  | 2,060
WAHA [Member] | Gas Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | BTU | [3] |  | 13,908
GD Waha [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 12.00%
IF Waha [Member] |  |  |
Derivative Financial Instruments |  |  |
Index percent of natural gas fixed swaps |  |  | 10.00%
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 877
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 12.29
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 907
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 12.34
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 896
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 12.36
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 711
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 11.38
OPIS Ethane Purity Mont Belvieu [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 3,391
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 561
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 31.32
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 637
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 31.29
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 651
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 31.64
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 0.00
OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 1,849
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 38
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 35.64
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 39
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 35.64
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 39
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 35.64
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 0.00
OPIS Normal Butane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 116
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 29
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 35.70
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 30
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 35.70
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 29
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 35.70
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 0.00
OPIS Isobutane Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 88
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract Second Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 49
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 50.93
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract Third Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 50
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 50.93
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract Fourth Quarter of Current Fiscal Year [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 50
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 50.93
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 0
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  |  | 0.00
OPIS Natural Gasoline Mont Belvieu Non-TET [Member] | NGL Swaps Contracts [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  |  | 149
Subsequent Event [Member] | NYMEX Oil Swap Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,600 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 61.49 |
Subsequent Event [Member] | NYMEX Oil Collar Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 1,700 |
Derivative, Weighted- Average Floor Price | $ / Barrels |  | 55.00 |
Derivative, Weighted-Average Ceiling Price | $ / Barrels |  | 65.07 |
Subsequent Event [Member] | OPIS Propane Mont Belvieu Non-TET [Member] | NGL Swaps Contract, Year 2 [Member] |  |  |
Derivative Financial Instruments |  |  |
Derivative, Nonmonetary Notional Amount, Volume |  | 600 |
Derivative, Swap Type, Average Fixed Price | $ / Barrels |  | 28.10 |
[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 March 31, 2019, total volumes for gas swaps are comprised of 78 percent IF HSC, 12 percent GD Waha, and 10 percent IF Waha.

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