Note 2 - Accounts Receivable (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Accounts Receivable, Allowance for Credit Loss, Writeoff	$ 9,233	$ 1,162
Minimum [Member]
Allowance for Doubtful Accounts Receivable, Percent	1.00%
Maximum [Member]
Allowance for Doubtful Accounts Receivable, Percent	10.00%