Note 3 - Short-term Investments (Tables)

6 Months Ended

Mar. 31, 2023

Notes Tables

Schedule of Available-for-Sale Securities Reconciliation [Table Text Block]

	September 30, 2022 (in thousands)
	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Short-term investments:
Corporate bonds	$	909	$	—	$	(15	)	$	894