Supplementary Information on Oil and Gas Operations—Unaudited (Tables)

12 Months Ended

Dec. 31, 2018

Oil and Gas Exploration and Production Industries Disclosures [Abstract]

Costs incurred in oil and gas property acquisition

The following tables disclose certain financial data relative to the Company’s oil and gas producing activities, which are located onshore and offshore in the continental United States:

Costs Incurred in Oil and Gas Property Acquisition, Exploration and Development Activities

(amounts in thousands)

	For the Year-Ended December 31,
	2018			2017			2016
Acquisition costs:
Proved	$	241		$	1,330		$	3,346
Unproved (1)	6,190			12,762			2,197
Divestiture of proved leasehold	(2,604		)	(4,795		)	(7,000		)
Exploration costs:
Proved	(51		)	9,466			715
Unproved	233			(287		)	603
Development costs (2)	(18,928		)	32,622			1,522
Capitalized general and administrative and interest costs	8,070			8,269			7,558
Total costs incurred	$	(6,849	)	$	59,367		$	8,941

	For the Year-Ended December 31,
	2018			2017			2016
Accumulated depreciation, depletion and amortization (DD&A)
Balance, beginning of year	$	(1,285,660	)	$	(1,243,286	)	$	(1,157,455	)
Provision for DD&A	(22,410		)	(31,667		)	(27,962		)
Ceiling test writedown	—			—			(40,304		)
Sale of proved properties and other (3)	6,478			(10,707		)	(17,565		)
Balance, end of year	$	(1,301,592	)	$	(1,285,660	)	$	(1,243,286	)
DD&A per Mcfe	$	1.05		$	1.15		$	1.19

(1) During 2017, the Company acquired approximately 24,600 gross acres for approximately $9.3 million in cash and 2.0 million shares of common stock. In total for 2017 and 2018, the Company has invested approximately $15.0 million in leasing costs and geological and engineering data.

(2) During 2018, the Company sold its Gulf of Mexico properties and removed approximately $28.2 million of future discounted asset retirement obligations, which was recorded as a reduction in the capitalized costs of oil and gas properties.

(3) During 2018, the Company sold its Gulf of Mexico properties, receiving no cash consideration and funding amounts related to the future abandonment costs for the properties and purchase price adjustments. During 2017, the Company sold its East Lake Verret assets for net proceeds of approximately $2.2 million and its East Texas saltwater disposal assets for net proceeds of $8.5 million. During 2016, the Company sold its remaining Oklahoma producing assets for net proceeds of $17.6 million.

Schedule of proved developed reserve quantities

The following table sets forth an analysis of the Company’s estimated quantities of net proved and proved developed oil (including condensate), gas and natural gas liquid reserves, all located onshore and offshore in the continental United States:

	Oil in MBbls		NGL in MMcfe		Natural Gas in MMcf		Total Reserves in MMcfe
Proved reserves as of December 31, 2015	1,806		34,826		132,344		178,004
Revisions of previous estimates	247		(4,380	)	(11,854	)	(14,748	)
Extensions, discoveries and other additions	—		—		1,485		1,485
Sale of reserves in place	(154	)	—		(24,834	)	(25,759	)
Production	(502	)	(3,871	)	(16,617	)	(23,501	)
Proved reserves as of December 31, 2016	1,397		26,575		80,524		115,481
Revisions of previous estimates	308		(7,269	)	381		(5,040	)
Extensions, discoveries and other additions	777		4,565		64,704		73,931
Purchase of producing properties	48		—		473		761
Sale of reserves in place	(90	)	—		(1,033	)	(1,573	)
Production	(592	)	(4,450	)	(19,611	)	(27,613	)
Proved reserves as of December 31, 2017	1,848		19,421		125,438		155,947
Revisions of previous estimates	130		(1,469	)	2,737		2,044
Extensions, discoveries and other additions	41		2,929		7,947		11,121
Sale of reserves in place	(507	)	(486	)	(13,945	)	(17,472	)
Production	(326	)	(3,373	)	(16,013	)	(21,335	)
Proved reserves as of December 31, 2018	1,186		17,022		106,164		130,305
Proved developed reserves
As of December 31, 2016	1,212		13,073		47,349		67,694
As of December 31, 2017	1,078		12,564		57,409		76,441
As of December 31, 2018	567		10,220		47,516		61,143
Proved undeveloped reserves
As of December 31, 2016	185		13,502		33,175		47,787
As of December 31, 2017	770		6,857		68,029		79,506
As of December 31, 2018	619		6,802		58,648		69,162

Standardized measure of discounted future cash flows

Standardized Measure

	December 31,
	2018			2017			2016
Future cash flows	$	482,766		$	539,244		$	299,035
Future production costs	(171,999		)	(184,171		)	(117,283		)
Future development costs	(73,258		)	(128,447		)	(83,720		)
Future income taxes	—			—			—
Future net cash flows	237,509			226,626			98,032
10% annual discount	(113,484		)	(99,329		)	(30,763		)
Standardized measure of discounted future net cash flows	$	124,025		$	127,297		$	67,269

Schedule of changes in standardized measure of discounted future net cash flows

Changes in Standardized Measure

	Year Ended December 31,
	2018			2017			2016
Standardized measure at beginning of year	$	127,297		$	67,269		$	127,685
Sales and transfers of oil and gas produced, net of production costs	(64,148		)	(70,362		)	(35,993		)
Changes in price, net of future production costs	18,542			53,516			(30,427		)
Extensions and discoveries, net of future production and development costs	2,983			50,977			864
Changes in estimated future development costs, net of development costs incurred during this period	16,241			17,144			26,356
Revisions of quantity estimates	2,755			(7,482		)	(14,889		)
Accretion of discount	12,730			6,727			12,769
Purchase of reserves in place	—			549			—
Sale of reserves in place	1,614			(1,305		)	(16,701		)
Changes in production rates (timing) and other	6,011			10,264			(2,395		)
Net increase (decrease) in standardized measure	(3,272		)	60,028			(60,416		)
Standardized measure at end of year	$	124,025		$	127,297		$	67,269

Average sales price and average production costs

The historical twelve-month, first day of the month, average prices of oil, gas and natural gas liquids used in determining standardized measure were:

	2018	2017	2016
Oil, $/Bbl	$68.71	$52.49	$40.85
Ngls, $/Mcfe	4.08	3.23	2.40
Natural Gas, $/Mcf	3.13	3.03	1.82