Asset Retirement Obligations (Schedule Of Asset Retirement Obligations) (Details) - USD ($) $ in Thousands		1 Months Ended	8 Months Ended		9 Months Ended
	Sep. 01, 2020	Sep. 30, 2020	Aug. 31, 2020		Sep. 30, 2019
ARO liability, Beginning Balance:	$ 38,984	$ 38,984	$ 66,627		$ 64,208
Accretion of discount		(116)	(1,545)		(1,770)
Liability incurred		141	465		4,325
Liability settled		(51)	(838)		(2,805)
Liability sold		0	(487)		(1,721)
Revision of estimates		125	(28,328)	[1]	(1,705)	[2]
ARO, Ending Balance:	24,591	24,922	$ 38,984		64,072
Fresh-Start adjustments	$ (14,393)
Less: current portion		2,186			3,033
Total long-term ARO		$ 22,736			$ 61,039

[1] Plugging liability estimates were revised in 2020 for updates in the cost of services used to plug wells over the preceding year and estimated dates to be plugged.

[2] Plugging liability estimates were revised in 2019 for updates in the cost of services used to plug wells over the preceding year. We had various upward and downward adjustments.