Note 2 - Revenue from Contracts with Customers - Deferred Costs of Revenue Balances Included in Prepaid Expenses (Details) - USD ($)	3 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020
Balance, deferred costs of revenue	$ 31,251	$ 89,068	$ 246,351	$ 453,607
Defered costs added	11,188	17,406	2,472	181
Deferred costs expensed	(16,681)	(75,223)	(192,548)	(207,437)
Balance, deferred costs of revenue	$ 25,758	$ 31,251	$ 56,275	$ 246,351