SUPPLEMENTAL OIL AND GAS DISCLOSURES (Unaudited) (Components Of Changes In Standardized Measure Of Discounted Future Net Cash Flows) (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Feb. 08, 2018	Dec. 31, 2018	Dec. 31, 2019
Components of changes in standardized measure of discounted future net cash flows
Balance at beginning of period	$ 1,105,922	$ 1,179,886	$ 714,283
Sales and transfers of oil and gas produced, net of production costs	(30,391)	(278,091)	(253,582)
Net changes in prices and production costs	71,334	38,963	(270,712)
Revisions of previous quantity estimates	10,887	(1,120,097)	(129,305)
Purchases of reserves in-place	0	24,376	0
Sales of reserves-in-place	(4,807)	0	0
Current year discoveries and extensions, less related costs	0	684,700	134,451
Changes in estimated future development costs	491	(39,069)	473
Development costs incurred during the period	0	160,583	84
Accretion of discount	110,592	117,989	81,285
Net change in income taxes	0	(98,568)	79,134
Change in production rate (timing) and other	(84,142)	43,611	(29,200)
Net change	73,964	(465,603)	(387,372)
Balance at end of period	$ 1,179,886	$ 714,283	$ 326,911