Note 10 - Equity Transactions - Summary of Warrants Outstanding, Exercise Price, and Expiration Dates (Details) - $ / shares	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Warrants Issued (in shares)	15,745,846	2,045,846	2,048,186
Warrants Expiring in February 2024 [Member]
Warrants Issued (in shares)	58,930
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 35
Warrants Expiring in October 2024 [Member]
Warrants Issued (in shares)	2,400
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 25
Warrants Expiring in October 2024, Two [Member]
Warrants Issued (in shares)	57,600
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 25
Warrants Expiring in November 2024 [Member]
Warrants Issued (in shares)	302,379
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 9.37
Warrants Expiring in April 23, 2025 [Member]
Warrants Issued (in shares)	80,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 25
Warrants Expiring in December, 2025 [Member]
Warrants Issued (in shares)	35,200
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 65
Warrants Expiring in September 2025 [Member]
Warrants Issued (in shares)	2,223
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 11
Warrants Expiring in September 2027 [Member]
Warrants Issued (in shares)	283,111
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 15
Warrant Expiring in December 2025, Two [Member]
Warrants Issued (in shares)	1,078,796
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 5
Warrants Expiring in December 2025, Third [Member]
Warrants Issued (in shares)	57,500
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 6.25
Warrants Expiring in January 2026 [Member]
Warrants Issued (in shares)	2,608,596
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 1.36
Warrants Expiring in December 2027 [Member]
Warrants Issued (in shares)	156,522
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 2.02
Warrants Expiring in January 2028 [Member]
Warrants Issued (in shares)	2,608,596
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 1.36
Warrants Expiring in October 2028 [Member]
Warrants Issued (in shares)	3,695,227
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.95
Warrants Expiring in April 2030 [Member]
Warrants Issued (in shares)	718,566
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.71
Warrants Expiring in August 2030 [Member]
Warrants Issued (in shares)	4,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 1.25