SUPPLEMENTAL OIL AND GAS INFORMATION (UNAUDITED) - Proved Reserve Data (Details) bbl in Thousands, Mcf in Thousands, Boe in Thousands	12 Months Ended
	Dec. 31, 2019 Boe Mcf bbl	Dec. 31, 2019 Boe bbl Mcf	Dec. 31, 2019 Boe Mcf bbl	Dec. 31, 2019 Boe MMBoe Mcf bbl	Dec. 31, 2018 Boe Mcf bbl	Dec. 31, 2018 Boe bbl Mcf	Dec. 31, 2018 Boe Mcf bbl	Dec. 31, 2018 Boe MMBoe Mcf bbl	Dec. 31, 2017 Boe Mcf bbl	Dec. 31, 2017 Boe bbl Mcf	Dec. 31, 2017 Boe Mcf bbl	Dec. 31, 2017 Boe MMBoe Mcf bbl	Dec. 31, 2016 Boe bbl Mcf
Natural Gas
Proved Developed and Undeveloped Reserves [Roll Forward]
Proved Developed and Undeveloped Reserves, Beginning Balance | Mcf	135,066				78,121				46,832
Revisions of Previous Estimates | Mcf	(5,146)				426				8,839
Extensions, Discoveries and Other Additions | Mcf	22,019				28,348				27,637
Purchases of Minerals in Place | Mcf	53,969				37,397
Production | Mcf	(16,591)				(9,225)				(5,188)
Proved Developed and Undeveloped Reserves, Ending Balance | Mcf	189,318				135,066				78,121
Proved Developed Reserves | Mcf	116,846	116,846	116,846	116,846	82,315	82,315	82,315	82,315	46,518	46,518	46,518	46,518	32,808
Proved Undeveloped Reserve | Mcf	72,473	72,473	72,473	72,473	52,752	52,752	52,752	52,752	31,603	31,603	31,603	31,603	14,024
Oil
Proved Developed and Undeveloped Reserves [Roll Forward]
Proved Developed and Undeveloped Reserves, Beginning Balance | bbl		112,973				62,812				46,275
Revisions of Previous Estimates | bbl		(15,497)				3,470				890
Extensions, Discoveries and Other Additions | bbl		19,992				28,516				20,184
Purchases of Minerals in Place | bbl		25,611				25,965
Production | bbl		(11,325)				(7,790)				(4,537)
Proved Developed and Undeveloped Reserves, Ending Balance | bbl		131,754				112,973				62,812
Proved Developed Reserves | bbl	77,160	77,160	77,160	77,160	62,497	62,497	62,497	62,497	38,593	38,593	38,593	38,593	32,245
Proved Undeveloped Reserve | bbl	54,594	54,594	54,594	54,594	50,476	50,476	50,476	50,476	24,220	24,220	24,220	24,220	14,030
Proved Developed and Undeveloped Reserve (Energy) [Roll Forward]
Proved Developed and Undeveloped Reserves, Beginning Balance | Boe			135,484				75,832				54,081
Revisions of Previous Estimates			(16,355)	(16.4)			3,541	3.5			2,363	2.4
Extensions, Discoveries and Other Additions | Boe			23,662				33,241				24,791
Purchases of Minerals in Place			34,606	34.6			32,198	32.2
Production | Boe			(14,091)				(9,328)				(5,402)
Proved Developed and Undeveloped Reserves, Ending Balance | Boe			163,307				135,484				75,832
Proved Developed Reserves | Boe	96,634	96,634	96,634	96,634	76,216	76,216	76,216	76,216	46,346	46,346	46,346	46,346	37,713
Proved Undeveloped Reserves | Boe	66,673	66,673	66,673	66,673	59,268	59,268	59,268	59,268	29,487	29,487	29,487	29,487	16,368