K. QUARTERLY DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 138	$ 167	$ 173	$ 204	$ 159	$ 194	$ 243	$ 195	$ 185	$ 190	$ 170	$ 219	$ 682	$ 791	$ 764
Operating (expense)	(144)	(186)	(239)	(275)	(261)	(254)	(256)	(256)	(327)	(295)	(233)	(396)	(1,197)	(4,061)	(1,533)
Corporate general and administrative expense	(71)	(99)	(108)	(75)	(91)	(95)	(122)	(100)	(33)	(52)	(101)	(166)	(353)	(408)	(352)
Gain on prepayment of debt									888						888
Gain on sale of land									50						50
Impairment of natural gas and oil properties					(2,626)									(2,626)
Recovery of bad debt
Other income (expense) net	22	(3)		12	(30)	65	11	(11)	(80)	(13)	(7)	(10)	31	29	813
Net income (loss) from continuing operations					(2,849)	(90)	(124)	(172)	738	(170)	(171)	(353)	(484)	(3,241)	44
Net income (loss) from discontinued operations					(2)	(11)	(11)	13	(97)	6	38	57		(5)	4
Income (loss) allocable to common shareholders	$ (55)	$ (121)	$ (174)	$ (134)	$ (2,851)	$ (101)	$ (135)	$ (159)	$ 641	$ (164)	$ (133)	$ (296)	$ (484)	$ (484)	$ (3,246)	$ 48
Income (loss) per common share - basic	$ 0.00	$ (0.06)	$ (0.08)	$ (0.07)	$ (1.39)	$ (0.05)	$ (0.07)	$ (0.08)	$ 0.32	$ (0.08)	$ (0.07)	$ (0.15)

The amount of gain received due to prepayment of debt during the period.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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Amount of gain (loss) on sale or disposal of proven and unproven oil and gas properties.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount after tax of income (loss) from continuing operations attributable to the parent.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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Amount of recoveries of premiums receivable that were previously written off as bad debts.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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