Note 1 - Basis of Presentation and Significant Accounting Policies - Computation of Basic and Diluted Weighted Average Shares Used in Earnings Per Share Calculations (Details) - shares	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
– basic (in shares)	9,114,451	8,040,513	9,095,810	8,001,723
Effect of dilutive options and warrants (treasury method) (in shares)	0	517,275	0	450,190
– diluted (in shares)	9,114,451	8,557,788	9,095,810	8,451,913
Options, warrants and convertible shares outstanding during each period, but not included in the computation of diluted net loss per share because they are antidilutive (in shares)	2,919,809	1,036,907	2,919,809	1,289,407