Derivative Financial Instruments Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, (Gain) Loss [Line Items]
Derivative settlement (gain) loss	$ 213,555	$ (70,305)	$ 480,262	$ (286,270)
Net derivative (gain) loss	209,146	63,871	924,183	(314,269)
Oil Contracts [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Derivative settlement (gain) loss	154,113	(68,907)	344,740	(261,095)
Net derivative (gain) loss	68,194	30,641	611,224	(360,649)
Gas Contracts [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Derivative settlement (gain) loss	35,757	(896)	88,437	(16,575)
Net derivative (gain) loss	109,802	31,548	220,088	46,537
NGL Contracts [Member]
Derivative Instruments, (Gain) Loss [Line Items]
Derivative settlement (gain) loss	23,685	(502)	47,085	(8,600)
Net derivative (gain) loss	$ 31,150	$ 1,682	$ 92,871	$ (157)