Supplemental Oil And Natural Gas Disclosures (Components Of The Standardized Measure Of Discounted Future Net Cash Flows) (Details) $ in Thousands	1 Months Ended	3 Months Ended	11 Months Ended	12 Months Ended
	Feb. 08, 2018 USD ($) $ / bbl $ / MMcf	Mar. 31, 2018 $ / bbl	Dec. 31, 2018 USD ($) $ / bbl $ / MMcf	Dec. 31, 2017 USD ($) $ / bbl $ / MMcf	Dec. 31, 2016 USD ($) $ / bbl $ / MMcf	Dec. 31, 2015 USD ($)
Components of the standardized measure of discounted future net cash flows
Future cash flows			$ 2,446,888
Future production costs			(1,214,479)
Future development costs			(23,183)
Future taxes on income			0
Future net cash flows			1,209,226
Discount to present value at 10 percent per annum			(396,375)
Standardized measure of discounted future net cash flows	$ 1,179,886		$ 812,851
Base price for crude oil, per Bbl, in the above computation was | $ / bbl		40	65.56
Base price for natural gas, per Mcf, in the above computation was | $ / MMcf			3.10
Base Price Per Unit For Natural Gas Liquids | $ / MMcf			22.44
Predecessor
Components of the standardized measure of discounted future net cash flows
Future cash flows	5,798,886			$ 5,799,753	$ 3,547,130
Future production costs	(2,556,361)			(2,617,476)	(1,811,683)
Future development costs	(965,780)			(1,035,481)	(709,738)
Future taxes on income	0			0	0
Future net cash flows	2,276,745			2,146,796	1,025,709
Discount to present value at 10 percent per annum	(1,096,859)			(1,040,874)	(467,101)
Standardized measure of discounted future net cash flows	$ 1,179,886			$ 1,105,922	$ 558,608	$ 629,596
Base price for crude oil, per Bbl, in the above computation was | $ / bbl	52.89			51.34	42.75
Base price for natural gas, per Mcf, in the above computation was | $ / MMcf	2.99			2.98	2.49
Base Price Per Unit For Natural Gas Liquids | $ / bbl	27.48			26.06	15.18