Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments - Fair value gains (losses) (Details)

v3.19.1
Derivative Instruments - Fair value gains (losses) (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Summary of realized and unrealized gains (losses) on derivative instruments    
Commodity derivative fair value gains (losses) $ (77,368) $ 22,437
Marketing derivative fair value gains 91,186 94,234
Revenue    
Summary of realized and unrealized gains (losses) on derivative instruments    
Commodity derivative fair value gains (losses) $ (77,368) 22,437
Marketing derivative fair value gains   $ 94,234