Quarterly report pursuant to Section 13 or 15(d)

FAIR VALUE - Assets and Liabilities Accounted For At Fair Value On A Recurring Basis (Details)

v3.21.1
FAIR VALUE - Assets and Liabilities Accounted For At Fair Value On A Recurring Basis (Details) - Recurring - USD ($)
$ in Thousands
Mar. 31, 2021
Dec. 31, 2020
Quoted Prices In Active Markets for Identical Assets (Liabilities) (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) $ 0 $ 0
Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) (94,734) 33,664
Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Commodity Contract | Current Asset | Quoted Prices In Active Markets for Identical Assets (Liabilities) (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Commodity Contract | Current Asset | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 2,005 51,290
Commodity Contract | Current Asset | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Commodity Contract | Noncurrent Asset | Quoted Prices In Active Markets for Identical Assets (Liabilities) (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Commodity Contract | Noncurrent Asset | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 356 111
Commodity Contract | Noncurrent Asset | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Commodity Contract | Current Liabilities | Quoted Prices In Active Markets for Identical Assets (Liabilities) (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Commodity Contract | Current Liabilities | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) (34,508) (2,504)
Commodity Contract | Current Liabilities | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Commodity Contract | Noncurrent Liabilities | Quoted Prices In Active Markets for Identical Assets (Liabilities) (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Commodity Contract | Noncurrent Liabilities | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) (61,808) (14,214)
Commodity Contract | Noncurrent Liabilities | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Interest Rate Contract | Current Liabilities | Quoted Prices In Active Markets for Identical Assets (Liabilities) (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Interest Rate Contract | Current Liabilities | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) (600) (574)
Interest Rate Contract | Current Liabilities | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Interest Rate Contract | Noncurrent Liabilities | Quoted Prices In Active Markets for Identical Assets (Liabilities) (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) 0 0
Interest Rate Contract | Noncurrent Liabilities | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) (179) (445)
Interest Rate Contract | Noncurrent Liabilities | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets (liabilities) $ 0 $ 0