Note 2 - Revenue Recognition (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2022
Contract with Customer, Liability, Current	$ 500		$ 500		$ 0
Capitalized Contract Cost, Net, Current	100		100		$ 0
Contract with Customer, Liability, Revenue Recognized	0		0
Contract with Customer, Liability, Cost of Revenue Recognized	0	$ 0	0	$ 0
Revenue, Remaining Performance Obligation, Amount	$ 0		$ 0