Note 2 - Revenue Recognition - Revenue by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Total revenue	$ 24,270	$ 31,370	$ 74,302	$ 62,479
Product [Member]
Total revenue	19,497	17,701	63,211	37,249
Asia [Member] | Product [Member]
Total revenue	3,672	1,443	35,888	7,977
CANADA | Product [Member]
Total revenue	1,002	333	2,228	1,094
Europe [Member] | Product [Member]
Total revenue	1,507	1,792	2,885	2,926
UNITED STATES | Product [Member]
Total revenue	12,831	13,479	21,249	24,070
Other [Member] | Product [Member]
Total revenue	$ 485	$ 654	$ 961	$ 1,182