SUPPLEMENTAL OIL AND GAS DISCLOSURES (Unaudited) (Estimated Quantities of Proved Reserves) (Details) MMcf in Thousands, MMBoe in Thousands, MBbls in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Feb. 08, 2018 MMBoe MBbls MMcf	Dec. 31, 2018 MMBoe MBbls MMcf	Dec. 31, 2019 MMBoe MBbls MMcf	Dec. 31, 2017 MBbls MMcf
Revisions of previous quantity estimates and other:
Proved Developed Reserves, Beginning of Period | MMBoe		51,731
Proved Undeveloped Reserves, Beginning of Period | MMBoe		124,685
Total, Proved Developed and Undeveloped Reserves, Beginning of Period | MMBoe		176,416
Proved Developed Reserves, Production | MMBoe		(10,140)
Proved Undeveloped Reserves, Production | MMBoe		0
Total, Production | MMBoe		(10,140)
Proved Developed Reserves, Purchases in place, discoveries and extensions | MMBoe		35,096
Proved Undeveloped Reserves, Purchases in place, discoveries and extensions | MMBoe		47,092
Total, Purchases in place, discoveries and extensions | MMBoe		82,188
Proved Developed Reserves, Lower estimated recoveries identified as a result of 2018 drilling program | MMBoe		(31,964)
Proved Undeveloped Reserves, Lower estimated recoveries identified as a result of 2018 drilling program | MMBoe		(69,534)
Total, Lower estimated recoveries identified as a result of 2018 drilling program | MMBoe		(101,498)
Proved Developed Reserves, Higher average commodity prices in Successor Period compared to 2017 | MMBoe		5,367
Proved Undeveloped Reserves, Higher average commodity prices in Successor Period compared to 2017 | MMBoe		5,829
Total, Higher average commodity prices in Successor Period compared to 2017 | MMBoe		11,196
Proved Developed Reserves, Transfers of PUDs to proved developed reserves | MMBoe		18,999
Proved Undeveloped Reserves, Transfers of PUDs to proved developed reserves | MMBoe		(18,999)
Total, Transfers of PUDs to proved developed reserves | MMBoe		0
Proved Developed Reserves, Derecognition of PUDs due to significant concerns about ability to fund development of those reserves | MMBoe		0
Proved Undeveloped Reserves, Derecognition of PUDs due to significant concerns about ability to fund development of those reserves | MMBoe		(89,073)
Total, Proved Undeveloped Reserves, Derecognition of PUDs due to significant concerns about ability to fund development of those reserves | MMBoe		(89,073)
Proved Developed Reserves, End of Period | MMBoe	51,731		69,089
Proved Undeveloped Reserves, End of Period | MMBoe	124,685		0
Total, Proved Developed and Undeveloped Reserves, End of Period | MMBoe	176,416		69,089
Oil
Total Proved Reserves:
Proved Reserves, Beginning Balance	73,518	71,705	25,272
Production	(521)	(5,053)	(5,885)
Purchases in place		2,658
Discoveries and extensions		30,026	4,265
Sales of reserves in place	(1,667)
Revisions of previous quantity estimates and other	375	(74,064)	(6,736)
Proved Reserves, Ending Balance	71,705	25,272	16,916
Proved Developed Reserves	19,345	25,272	16,916	20,347
Proved Undeveloped Reserve	52,360	0	0	53,171
Natural gas
Total Proved Reserves:
Proved Reserves, Beginning Balance | MMcf	433,519	410,802	144,148
Production | MMcf	(1,984)	(16,913)	(24,802)
Purchases in place | MMcf		13,331
Discoveries and extensions | MMcf		155,306	24,351
Sales of reserves in place | MMcf	(24,239)
Revisions of previous quantity estimates and other | MMcf	3,506	(418,378)	(29,254)
Proved Reserves, Ending Balance | MMcf	410,802	144,148	114,443
Proved Developed Reserves | MMcf	126,231	144,148	114,443	150,183
Proved Undeveloped Reserve | MMcf	284,571	0	0	283,336
Natural gas liquids
Total Proved Reserves:
Proved Reserves, Beginning Balance	36,887	36,244	19,792
Production	(161)	(2,268)	(2,760)
Purchases in place		1,751
Discoveries and extensions		19,646	2,835
Sales of reserves in place	(771)
Revisions of previous quantity estimates and other	289	(35,581)	(9,352)
Proved Reserves, Ending Balance	36,244	19,792	10,515
Proved Developed Reserves	11,348	19,792	10,515	12,180
Proved Undeveloped Reserve	24,896	0	0	24,707
BOE
Total Proved Reserves:
Proved Reserves, Beginning Balance	182,658	176,416	69,089
Production	(1,012)	(10,140)	(12,779)
Purchases in place		6,631
Discoveries and extensions		75,557	11,159
Sales of reserves in place	(6,478)
Revisions of previous quantity estimates and other	1,248	(179,375)	(20,964)
Proved Reserves, Ending Balance	176,416	69,089	46,505
Proved Developed Reserves	51,731	69,089	46,505	57,557
Proved Undeveloped Reserve	124,685	0	0	125,101