Note 3 - Revenue Recognition (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2018	Jan. 07, 2019	Dec. 31, 2017
Maintenance Plan, Service Requirement, Period Subsequent to One Year Anniversary of Invoice	1 year
Standard Product Warranty, Term	1 year
Accounts Receivable, Net, Current, Total	$ 232,602	$ 232,602	$ 137,499
Contract with Customer, Liability, Current	$ 23,065		$ 6,663
Maintenance [Member]
Revenue, Performance Obligation, Timing	1 year
Minimum [Member]
Standard Payment Term for Customers	30 days
Maximum [Member]
Standard Payment Term for Customers	60 days