Note 4 - Accounts Receivable - Accounts Receivable (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Accounts receivable	$ 1,269,656	$ 2,446,486
Expected credit losses	(53,633)	(53,708)
Net accounts receivable	$ 1,216,023	$ 2,392,778