Note 5 - Property and Equipment (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Gain (Loss) on Disposition of Oil and Gas and Timber Property, Total	$ 75,926	$ 878,320
Depreciation, Depletion and Amortization, Total	616	8,735
Land [Member]
Gain (Loss) on Disposition of Oil and Gas and Timber Property, Total	$ 75,926	878,320
Land [Member] \| Partially Owned Properties [Member]
Gain (Loss) on Disposition of Oil and Gas and Timber Property, Total		$ 767,147
Investment Owned, Percent of Net Assets	6.25%

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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Amount of gain (loss) on sale or disposal of oil and gas property or timber property.

+ References

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Percent of net assets at close of period. For schedules of investments that are categorized, each category has a percent of net assets for the aggregated value of the Investments in the category.

+ References

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