Note 9 - Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2021

Notes Tables

Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]

					Weighted
			Weighted		Average
			Average		Remaining
			Exercise		Contractual
Warrants	Shares		Price		Life (Years)
Outstanding at December 31, 2020		1,043,667	$	3.73		4.7
Issued		150,418		2.51		4.9
Outstanding at March 31, 2021		1,194,085	$	3.58		4.5
Exercisable at March 31, 2021		43,667	$	3.34		3.5