Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Mar. 31, 2023	Dec. 31, 2022
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized (in shares)	1,800,000	1,800,000
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized (in shares)	500,000,000	500,000,000
Common Stock, Shares, Outstanding (in shares)	224,112,168	219,163,631
Common Stock, Shares, Issued (in shares)	224,112,168	219,163,631
Series A Preferred Stock [Member]
Preferred Stock, Shares Authorized (in shares)	300,000	300,000
Preferred Stock, Shares Issued (in shares)	130,106	133,423
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	130,106	133,423
Series B Preferred Stock [Member]
Preferred Stock, Shares Authorized (in shares)	1,500,000	1,500,000
Preferred Stock, Shares Issued (in shares)	0	0
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	0	0