SUPPLEMENTARY INFORMATION ON OIL AND NATURAL GAS EXPLORATION, DEVELOPMENT (Tables)

12 Months Ended

Dec. 31, 2019

Supplemental Oil And Gas Reserve Information [Abstract]

Costs incurred for and results of operations for oil and gas producing activities disclosure

The following table sets forth the costs incurred in the Company’s oil and natural gas acquisition, exploration and development activities and includes costs whether capitalized or expensed as well as revisions and additions to the estimated future asset retirement obligations:

	December 31,
	2019		2018
	(In thousands)
Acquisition costs:
Unproved properties	$	1,644	$	93,926
Proved properties	—		22,356
Exploration costs	40,284		89,351
Development costs	51,198		78,103
Total	$	93,126	$	283,736

The following table sets forth the results of operations for oil and natural gas producing activities:

	December 31,
	2019			2018
	(In thousands)
Revenues	$	66,063		$	70,216
Production costs	(16,127		)	(13,843		)
Production taxes	(3,302		)	(3,709		)
Accretion of asset retirement obligation	(433		)	(85		)
Depletion, depreciation and amortization	(33,071		)	(25,159		)
Full cost ceiling impairment	(228,324		)	—
Total	$	(215,194	)	$	27,420

Schedule of proved developed and undeveloped oil and gas reserve quantities

The following table provides a roll forward of the total proved reserves for the years ended December 31, 2019 and 2018, as well as proved developed and proved undeveloped reserves at the beginning and end of each respective year:

	Crude Oil (Bbls)		Natural Gas (Mcf)		NGLs (Bbls)
January 1, 2018	7,171,339		16,059,926		1,604,570
Extensions and discoveries	15,881,727		38,957,588		4,565,994
Purchase of reserves	1,883,047		8,897,115		682,964
Revisions of previous estimates	(2,641,353	)	17,690,723		1,769,448
Production	(1,089,724	)	(2,855,739	)	(246,425	)
December 31, 2018	21,205,036		78,749,613		8,376,551
Extensions and discoveries	856,838		2,477,061		190,203
Revisions of previous estimates	(15,596,115	)	(48,718,235	)	(6,067,700	)
Production	(1,130,855	)	(3,063,927	)	(220,832	)
December 31, 2019	5,334,904		29,444,512		2,278,222
Proved Developed Reserves, included above:
Balance, January 1, 2018	2,531,397		6,594,446		644,102
Balance, December 31, 2018	6,278,036		27,046,195		2,653,908
Balance, December 31, 2019	5,334,904		29,444,512		2,278,222
Proved Undeveloped Reserves, included above:
Balance, January 1, 2018	4,639,942		9,465,480		960,468
Balance, December 31, 2018	14,927,000		51,703,418		5,722,643
Balance, December 31, 2019	—		—		—

Standardized measure of discounted future cash flows relating to proved reserves disclosure

The standardized measure of discounted future net cash flows relating to proved oil, natural gas and NGL reserves is as follows:

	December 31,
	2019			2018
	(In thousands)
Future cash inflows	$	358,127		$	1,500,263
Future production costs	(176,498		)	(414,117		)
Future development costs	(7,284		)	(346,225		)
Future income tax expense	—			(62,842		)
Future net cash flows	174,345			677,079
10% discount to reflect timing of cash flows	(54,171		)	(384,345		)
Total	$	120,174		$	292,734

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

Changes in the standardized measure of discounted future net cash flows relating to proved oil, natural gas and NGL reserves are as follows:

	Year Ended December 31,
	2019			2018
	(In thousands)
Balance at beginning of period	$	292,734		$	68,812
Net changes in prices and production costs (1)	(275,539		)	24,261
Sales of oil and natural gas produced during the year, net	(42,442		)	(49,271		)
Changes in estimated future development costs (2)	272,579			(39,938		)
Net change due to extensions and discoveries	18,044			161,785
Net change due to purchases of minerals in place	—			55,278
Previously estimated development costs incurred during the year	36,298			68,349
Net changes due to revision of previous quantity estimates (3)	(255,125		)	28,350
Accretion of discount	29,273			6,881
Other - unspecified (4)	9,327			3,252
Net change in income taxes	35,025			(35,025		)
Balance at end of period	$	120,174		$	292,734

(1) Net changes from prices and production costs were primarily the result of a 19% decrease in oil and natural gas prices and 45% increase in production costs from December 31, 2018 to December 31, 2019.

(2) Future development costs decreased $272.6 million from December 31, 2018 to December 31, 2019. Our December 31, 2019 proved reserves report reflects the reclassification of all PUD reserves to unproved because of the uncertainty regarding the availability of capital for developing those reserves. Our December 31, 2018 proved reserves report included future development costs of $329.5 million associated with PUD reserves not included in our December 31, 2019 proved reserves report.

(3) Negative revisions for 2019 are primarily the result of the reclassification of proved undeveloped reserves to unproved as reflected in our December 31, 2019 reserves report.

(4) Other changes are the result of significant changes to our proved reserves from December 31, 2018 to December 31, 2019 and include significant estimates of the effects of changes in the economic lives of producing wells and reclassification of proved undeveloped reserves to unproved as reflected in our December 31, 2019 reserves report.