Note 10 - Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2020

Notes Tables

Schedule of Preferred Stock [Table Text Block]

	September 30, 2020				December 31, 2019
			Carrying				Carrying
	Shares		Value		Shares		Value
Series B Convertible Preferred Stock		100	$	76,095		100	$	76,095
Series H Convertible Preferred Stock		-		-		1,686		1,156,338
Series I Convertible Preferred Stock		-		-		700		700,000
Total		100	$	76,095		2,486	$	1,932,433

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

Warrant Description	Number of Shares		Exercise Price		Expiration
Series I Warrants		62,626	$	5.00	Oct-Dec 2024
June 2020 Warrants		120,000		5.00	Jun 2025
Pre-Funded Warrants		376,042		0.01	Perpetual
Unit, Conversion and Management Warrants		3,163,669		5.00	Sep 2025
Representative Warrants		128,000		5.50	Mar 2024
Total Warrants Outstanding at September 30, 2020		3,850,337
Weighted-Average Exercise Price	$	4.53
Weighted-Average Remaining Life (excluding Pre-Funded Warrants)(in years)		4.9