Note 1 - Description of Business and Basis of Presentation (Details Textual) - USD ($)	Nov. 04, 2021	Jan. 28, 2021	Nov. 09, 2021	Sep. 30, 2021
Equity Offering Sales Agreement, Aggregate Sales Price Value			$ 50,000,000.0
Revolving Credit Facility [Member]
Debt Instrument, Collateral Amount	$ 3,000,000	$ 750,000		$ 1,500,000
Line of Credit Facility, Commitment Fee Percentage		5.00%
Debt Instrument, Increase (Decrease) in Collateral Amount	$ 1,500,000