Stock-Based Compensation (Schedule Of Restricted Stock Awards) (Details) - USD ($) $ in Thousands	4 Months Ended	8 Months Ended		12 Months Ended
	Dec. 31, 2020	Aug. 31, 2020		Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Recognized stock compensation expense		$ 6,100	[1]	$ 12,800
Capitalized stock compensation cost for our oil and natural gas properties		0		2,400
Tax benefit on stock based compensation		1,500		$ 3,100
Acceleration of Predecessor stock compensation expense	$ 0	$ 1,431

[1] When the company's equity-based awards were cancelled on the Effective Date, we immediately recognized the expense for the cancelled awards of $1.4 million as reorganization costs, net.