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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under operating lease.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Note 9 - Commitments and Contingencies (Details Textual) bbl in Millions	3 Months Ended
	Mar. 31, 2021 USD ($) bbl	Dec. 31, 2020 USD ($)	Jan. 01, 2020 USD ($)
Contractual Obligation, Total	$ 760,000
Retained Earnings (Accumulated Deficit), Ending Balance	$ (102,465,000)	$ (107,209,000)
Accounting Standards Update 2016-02 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Retained Earnings (Accumulated Deficit), Ending Balance			$ 0
The Salt-Water Disposal Supply Agreement [Member]
Number of Barrels to be Delivered (Barrel of Oil) \| bbl	5.5
The Salt-Water Disposal Supply Agreement Due on September 30, 2021
Number of Barrels to be Delivered (Barrel of Oil) \| bbl	2.5
Number of Barrels, Delivered (Barrel of Oil) \| bbl	2.1
The Salt-Water Disposal Agreement Due on July 24, 2022 [Member]
Number of Barrels to be Delivered (Barrel of Oil) \| bbl	3.0
Number of Barrels, Delivered (Barrel of Oil) \| bbl	1.7
Other Noncurrent Assets [Member]
Operating Lease, Right-of-Use Asset	$ 371,000	506,000
Other Liabilities [Member]
Operating Lease, Liability, Total	374,000	508,000
Other Current Liabilities [Member]
Operating Lease, Liability, Noncurrent	322,000	430,000
Other Noncurrent Liabilities [Member]
Operating Lease, Liability, Noncurrent	$ 52,000	$ 78,000