Note 5 - Leases (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2023	Mar. 31, 2021	Sep. 30, 2023
Operating Lease, Right-of-Use Asset	$ 206		$ 295
General and Administrative Expense [Member]
Operating Lease, Expense	100
Office in Novato, California [Member]
Lessee, Operating Lease, Renewal Term (Year)		3 years
Operating Lease, Right-of-Use Asset		$ 1,100
Lease Expiration Date		Jul. 31, 2024
Other Long-term Operating Leases [Member]
Contractual Obligation	$ 0		$ 0