Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Abstract]
Net operating loss carryforwards	$ 9,119	$ 9,675
Oil and gas properties	1,054	1,327
Property, Plant and Equipment	(5)	(163)
Asset retirement obligation	500	592
Tax credits	65	130
Miscellaneous	36	45
Valuation allowance	(10,704)	(11,476)
Net deferred tax asset	$ 65	$ 130

Deferred Tax Assets, Oil And Gas Properties

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from asset retirement obligations. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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