Note 11 - Stockholders' Equity - Outstanding Warrants (Details) shares in Thousands	Sep. 30, 2023 $ / shares shares
Outstanding Warrants to Purchase Shares (in shares)	21,515
The 2020 Warrants [Member]
Outstanding Warrants to Purchase Shares (in shares)	6,490
Exercise Price (in dollars per share) | $ / shares	$ 1
The January 2021 Warrants [Member]
Outstanding Warrants to Purchase Shares (in shares)	4,500
Exercise Price (in dollars per share) | $ / shares	$ 1.055
March 2021 Warrants [Member]
Outstanding Warrants to Purchase Shares (in shares)	10,525
Exercise Price (in dollars per share) | $ / shares	$ 2.88