Quarterly report pursuant to Section 13 or 15(d)

Derivatives and Fair Value (Effect of Derivative Instruments on the Condensed Consolidated Statements of Operations) (Details)

v3.21.2
Derivatives and Fair Value (Effect of Derivative Instruments on the Condensed Consolidated Statements of Operations) (Details) - Crude Oil Swaps [Member] - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2021
Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]      
Derivative instruments gain (loss), net $ (5,147) $ (21,070) $ 6,583
Realized Gain (Loss) - Contract Settlements [Member]      
Derivative Instruments, Gain (Loss) [Line Items]      
Derivative instruments gain (loss), net (4,186) (10,189) 7,216
Unrealized Loss [Member]      
Derivative Instruments, Gain (Loss) [Line Items]      
Derivative instruments gain (loss), net $ (961) $ (10,881) $ (633)