Note 3 - Short-term Investments (Tables)

6 Months Ended

Mar. 31, 2024

Notes Tables

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

	As of March 31, 2024
	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Short-term investments:
Corporate bonds	$	21,937	$	—	$	(14	)	$	21,923
U.S. treasury securities and securities of U.S. government-sponsored agency		8,526		—		(1	)		8,525
Total	$	30,463	$	—	$	(15	)	$	30,448

	As of September 30, 2023
	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Short-term investments:
Corporate bonds	$	11,310	$	—	$	(15	)	$	11,295
U.S. treasury securities and securities of U.S. government-sponsored agency		3,622		4		—			3,626
Total	$	14,932	$	4	$	(15	)	$	14,921