Note 3 - Concentrations (Tables)

12 Months Ended

Dec. 31, 2019

Notes Tables

Schedules of Concentration of Risk, by Risk Factor [Table Text Block]

	December 31,
Accounts Receivable	2019			2018
Customer A		15	%		13	%
Customer B		13			13
Customer C		*			*
Customer D		19			*
Customer E		*			*

	Year Ended December 31,
Revenue	2019			2018			2017
Customer A		14	%		18	%		12	%
Customer B		*			*			12
Customer C		11			*			*
Customer D		*			*			*
Customer E		*			11			*