DERIVATIVE FINANCIAL INSTRUMENTS (Instruments) (Details) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended |
Apr. 30, 2020USD ($) | Jun. 30, 2021USD ($)item$ / item | Jun. 30, 2020USD ($) | Jun. 30, 2021USD ($)item$ / item | Jun. 30, 2020USD ($) |
Derivative Financial Instruments [Line Items] | | | | | |
Derivative settlement | $ | $ 145,000 | | | | |
Derivative gain (loss), net | $ | $ 13,000 | $ (255,409) | $ (6,632) | $ (402,102) | $ 224,739 |
Derivative instrument proceeds held in escrow | $ | | | $ 23,000 | | $ 23,000 |
Crude Oil [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 20,198,500 | | 20,198,500 | |
Crude Oil [Member] | 2021 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 3,588,000 | | 3,588,000 | |
Swap Price (in dollars per unit) | | 45.40 | | 45.40 | |
Crude Oil [Member] | 2021 [Member] | Two-way Collars [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 3,162,000 | | 3,162,000 | |
Floor Price (in dollars per unit) | | 41.64 | | 41.64 | |
Ceiling Price (in dollars per unit) | | 50.50 | | 50.50 | |
Crude Oil [Member] | 2022 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 630,000 | | 630,000 | |
Swap Price (in dollars per unit) | | 54.30 | | 54.30 | |
Crude Oil [Member] | 2022 [Member] | Two-way Collars [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 9,559,000 | | 9,559,000 | |
Floor Price (in dollars per unit) | | 43.22 | | 43.22 | |
Ceiling Price (in dollars per unit) | | 53.70 | | 53.70 | |
Crude Oil [Member] | 2023 [Member] | Two-way Collars [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 3,259,500 | | 3,259,500 | |
Floor Price (in dollars per unit) | | 46.79 | | 46.79 | |
Ceiling Price (in dollars per unit) | | 59.37 | | 59.37 | |
Crude Oil Differentials [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 76,500 | | 76,500 | |
Crude Oil Differentials [Member] | 2021 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 76,500 | | 76,500 | |
Swap Price (in dollars per unit) | | 1.95 | | 1.95 | |
Natural Gas [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 35,444,000 | | 35,444,000 | |
Natural Gas [Member] | 2021 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 8,970,000 | | 8,970,000 | |
Swap Price (in dollars per unit) | | 2.81 | | 2.81 | |
Natural Gas [Member] | 2021 [Member] | Two-way Collars [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 5,520,000 | | 5,520,000 | |
Floor Price (in dollars per unit) | | 2.60 | | 2.60 | |
Ceiling Price (in dollars per unit) | | 2.79 | | 2.79 | |
Natural Gas [Member] | 2022 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 5,259,000 | | 5,259,000 | |
Swap Price (in dollars per unit) | | 2.68 | | 2.68 | |
Natural Gas [Member] | 2022 [Member] | Two-way Collars [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 10,720,000 | | 10,720,000 | |
Floor Price (in dollars per unit) | | 2.35 | | 2.35 | |
Ceiling Price (in dollars per unit) | | 2.85 | | 2.85 | |
Natural Gas [Member] | 2023 [Member] | Two-way Collars [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 4,975,000 | | 4,975,000 | |
Floor Price (in dollars per unit) | | 2.37 | | 2.37 | |
Ceiling Price (in dollars per unit) | | 2.91 | | 2.91 | |
Natural Gas Basis [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 11,950,000 | | 11,950,000 | |
Natural Gas Basis [Member] | 2021 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 3,680,000 | | 3,680,000 | |
Swap Price (in dollars per unit) | | 0.18 | | 0.18 | |
Natural Gas Basis [Member] | 2022 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 3,530,000 | | 3,530,000 | |
Swap Price (in dollars per unit) | | 0.14 | | 0.14 | |
Natural Gas Basis [Member] | 2023 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 4,740,000 | | 4,740,000 | |
Swap Price (in dollars per unit) | | 0.07 | | 0.07 | |
NGL - Propane [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 23,100,000 | | 23,100,000 | |
NGL - Propane [Member] | 2021 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 19,320,000 | | 19,320,000 | |
Swap Price (in dollars per unit) | | 0.78 | | 0.78 | |
NGL - Propane [Member] | 2022 [Member] | Fixed Price Swaps [Member] | | | | | |
Derivative Financial Instruments [Line Items] | | | | | |
Aggregate notional amount of price risk derivatives | item | | 3,780,000 | | 3,780,000 | |
Swap Price (in dollars per unit) | | 0.81 | | 0.81 | |