Schedule of Changes in Estimated Proved Reserves (Details) Mcf in Thousands, MBoe in Thousands, MBbls in Thousands	12 Months Ended
	Dec. 31, 2020 MBoe MBbls Mcf	Dec. 31, 2019 MBoe MBbls Mcf	Dec. 31, 2018 MBoe MBbls Mcf
Proved developed and undeveloped reserves:
Beginning Balance | MBoe	23,027	27,740	32,192
Purchase of reserves in place | MBoe	72	56	50
Extensions and discoveries | MBoe	179	378
Revisions of previous estimates | MBoe	(1,590)	(3,373)	1,759
Divestiture of reserves | MBoe			(4,145)
Production | MBoe	(1,671)	(1,774)	(2,117)
Ending balance | MBoe	20,017	23,027	27,740
Proved developed reserves | MBoe	7,747	8,133	8,267
Proved undeveloped reserves | MBoe	12,270	14,894	19,473
Oil [Member]
Proved developed and undeveloped reserves:
Beginning Balance	12,596	15,212	18,076
Purchase of reserves in place	62	32	23
Extensions and discoveries	34	215
Revisions of previous estimates	(2,114)	(1,984)	421
Divestiture of reserves			(2,150)
Production	(836)	(879)	(1,158)
Ending balance	9,742	12,596	15,212
Proved developed reserves	3,291	3,900	3,857
Proved undeveloped reserves	6,451	8,696	11,355
Natural Gas [Member]
Proved developed and undeveloped reserves:
Beginning Balance | Mcf	46,270	56,185	58,790
Purchase of reserves in place | Mcf	62	70	83
Extensions and discoveries | Mcf	797	553
Revisions of previous estimates | Mcf	4,935	(6,950)	7,514
Divestiture of reserves | Mcf			(6,155)
Production | Mcf	(3,528)	(3,588)	(4,047)
Ending balance | Mcf	48,536	46,270	56,185
Proved developed reserves | Mcf	19,755	18,016	18,700
Proved undeveloped reserves | Mcf	28,781	28,254	37,485
Natural Gas Liquids [Member]
Proved developed and undeveloped reserves:
Beginning Balance	2,719	3,163	4,318
Purchase of reserves in place		12	13
Extensions and discoveries	12	71
Revisions of previous estimates	(298)	(230)	86
Divestiture of reserves			(969)
Production	(247)	(297)	(285)
Ending balance	2,186	2,719	3,163
Proved developed reserves	1,164	1,230	1,293
Proved undeveloped reserves	1,022	1,489	1,870