Note 9 - Equity (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Apr. 21, 2021	Sep. 28, 2020	Jun. 09, 2020	Jun. 08, 2020
Common and Preferred Stock, Shares Authorized (in shares)						350,000,000	179,000,000
Common Stock, Shares Authorized (in shares)	2,000,000,000		2,000,000,000	2,000,000,000.0	1,000,000,000.0	345,000,000
Preferred Stock, Shares Authorized (in shares)	5,000,000		5,000,000			5,000,000
Common Stock, Shares, Issued (in shares)	347,281,946		347,240,045
Common Stock, Shares, Outstanding, Ending Balance (in shares)	347,275,242		347,233,341
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)	3,150,000
Class of Warrant or Right, Exercisable (in shares)	1,466,680
Warrants and Rights Outstanding	$ 0
Warrants or Rights, Issued During Period (in shares)	0
Warrants or Rights, Cancelled During Period (in shares)	0
Warrants or Rights, Exercised During Period (in shares)	0
Warrants or Rights, Expired During Period (in shares)	0
Warrants [Member]
Share-Based Payment Arrangement, Expense	$ 15,000
Warrants Expiring Three Years From Initial Vesting [Member]
Class of Warrant or Right, Outstanding (in shares)	150,000
Minimum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.048
Maximum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	0.80
Weighted Average [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.10
Series A Preferred Stock [Member]
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	0
Series A-1 Preferred Stock [Member]
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	0
Series B Preferred Stock [Member]
Preferred Stock, Shares Authorized (in shares)	750,000		750,000
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	239,400		239,400
Dividends Payable	$ 21,000		$ 8,000
Conversion of Stock, Shares Converted (in shares)	0	0
Series C Preferred Stock [Member]
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	0
Series D Preferred Stock [Member]
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	23,469		23,216
Conversion of Stock, Shares Converted (in shares)	(0)