Supplemental Financial Data - Oil and Gas Producing Activities (unaudited) (Tables)

12 Months Ended

Dec. 31, 2019

Extractive Industries [Abstract]

Schedule of proved undeveloped and developed oil and gas reserves expected to be recovered from new wells

	2019												2018
	Oil			Natural Gas			NGL			Total			Oil			Natural Gas			NGL			Total
	MBbls			MMcf			MBbls			MMcfe			MBbls			MMcf			MBbls			MMcfe
Proved reserves, beginning of year		18,898			455,400			1,923			580,326			919			81,702			-			87,216
Revisions of previous estimates		(1,362	)		24,194			(618	)		12,310			(2,803	)		1,832			(1,147	)		(21,868	)
Extensions and discoveries		826			1,187			77			6,605			-			-			-			-
Production		(589	)		(21,436	)		(36	)		(25,182	)		(451	)		(4,798	)		(33	)		(7,702	)
Purchases of reserves in-place		-			-			-			-			21,233			376,664			3,103			522,680
Sales of reserves in-place		(31	)		(8,980	)		-			(9,166	)		-			-			-			-
Proved reserves, end of year		17,742			450,365			1,346			564,893			18,898			455,400			1,923			580,326
Proved developed reserves at:
End of year		12,972			444,104			936			527,555			14,336			450,424			1,472			545,272
Proved undeveloped reserves at:
End of year		4,770			6,261			410			37,338			4,562			4,976			451			35,054

Schedule of aggregate capitalized costs relating to oil and gas producing activities

(in thousands)	2019			2018
Oil and gas properties:
Proved oil and gas properties	$	351,488		$	347,059
Unproved properties		4,872			5,416
Accumulated depreciation, depletion, amortization and impairment		(109,344	)		(98,604	)
Total	$	247,016		$	253,871

Schedule of costs incurred in oil and gas property acquisition, exploration, and development activities

(in thousands)	2019		2018
Property acquisition costs:
Unevaluated properties	$	-	$	3,464
Proved properties and gathering facilities		-		63,517
Development costs		7,676		2,074
Gathering facilities		-		460
Asset retirement obligations		-		14,085
Total	$	7,676	$	83,600

Schedule of company's investment in unproved properties

(in thousands)	2019		2018		2017 and Prior
Acquisition costs	$	496	$	3,464	$	912

Schedule of results of operations from oil and gas producing activities

(in thousands)	2019		2018
Revenues:
Oil, gas and NGL sales, including commodity derivative gains and losses	$	96,885	$	52,946
Expenses:
Production expenses		41,307		22,226
Depletion expense		14,062		7,305
Accretion of asset retirement obligations		1,625		868
Total expenses		56,994		30,399
Results of operations from oil and gas producing activities	$	39,891	$	22,547
Depletion rate per Mcfe	$	0.56	$	0.89

Schedule of estimate of the current market value of the Company's proved reserves

	December 31,
(in thousands)	2019			2018
Future cash inflows	$	2,212,049		$	2,878,392
Future production costs		(1,306,608	)		(1,538,870	)
Future development costs		(77,952	)		(76,852	)
Future income taxes		(146,951	)		(258,277	)
Future net cash flows		680,538			1,004,393
10% annual discount		(408,690	)		(612,325	)
Standardized measure of discounted future net cash flows	$	271,848		$	392,068

Schedule of discounted future cash flows relating to proved oil and gas reserves

	December 31,
(in thousands)	2019			2018
Standardized measure of discounted future net cash flows, beginning of period	$	392,068		$	57,082
Sales of oil and gas, net of production costs and taxes		(49,746	)		(25,681	)
Price revisions		(158,799	)		133,789
Extensions, discoveries and improved recovery, less related costs		10,822			-
Changes in estimated future development costs		(3,041	)		(32,711	)
Development costs incurred during the period		6,685			926
Quantity revisions		5,565			(23,484	)
Accretion of discount		39,207			5,708
Net changes in future income taxes		39,929			(89,117	)
Purchases of reserves-in-place		-			391,877
Sales of reserves-in-place		(4,004	)		-
Changes in production rate timing and other		(6,838	)		(26,321	)
Standardized measure of discounted future net cash flows, end of period	$	271,848		$	392,068

Schedule of weighted averaged adjusted prices

	2019		2018
Oil (per Bbl)	$	55.69	$	65.56
Natural Gas (per Mcf)	$	2.58	$	3.10