Note 13 - Equity Offerings - Issuance of Warrants (Details) $ / shares in Units, $ in Millions	Dec. 31, 2024 $ / shares shares	Dec. 31, 2023 shares	Dec. 31, 2022 USD ($)
Number of shares (in shares) | shares	19,635,513	1,104,217
Exercise price (in dollars per share) | $ / shares
Placement Agent Warrant 1 [Member]
Number of shares (in shares) | shares	3,300
Exercise price (in dollars per share) | $ / shares	$ 312.5
Expiration (Year)	5 years
Value | $			$ 0.4
Placement Agent Warrant 1 [Member] | Measurement Input, Price Volatility [Member]
Assumptions			0.9325
Placement Agent Warrant 1 [Member] | Measurement Input, Risk Free Interest Rate [Member]
Assumptions			0.0181
Placement Agent Warrant 1 [Member] | Measurement Input, Expected Dividend Rate [Member]
Assumptions			0
Placement Agent Warrant 1 [Member] | Measurement Input, Expected Term [Member]
Assumptions			5
Placement Agent Warrant 2 [Member]
Number of shares (in shares) | shares	3,100
Exercise price (in dollars per share) | $ / shares	$ 175
Expiration (Year)	5 years
Value | $			$ 0.2
Placement Agent Warrant 2 [Member] | Measurement Input, Price Volatility [Member]
Assumptions			0.967
Placement Agent Warrant 2 [Member] | Measurement Input, Risk Free Interest Rate [Member]
Assumptions			0.0287
Placement Agent Warrant 2 [Member] | Measurement Input, Expected Dividend Rate [Member]
Assumptions			0
Placement Agent Warrant 2 [Member] | Measurement Input, Expected Term [Member]
Assumptions			5