Note 8 - Revenue Recognition (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Contract with Customer, Liability, Revenue Recognized	$ 293,653	$ 264,543
Revenue from Contract with Customer, Including Assessed Tax	1,592,711	1,579,281
Oil and Condensate [Member]
Revenue from Contract with Customer, Including Assessed Tax	981,931	980,786
Natural Gas, US Regulated [Member]
Revenue from Contract with Customer, Including Assessed Tax	565,112	541,273
Miscellaneous Oil and Gas Sales [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 45,668	$ 57,222