Note 1 - Significant Accounting Policies - Interest Income, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Interest expense	$ (5)	$ (10)
Interest income	1,160	712
Interest income, net	$ 1,155	$ 702

Amount of interest expense classified as operating and nonoperating. Includes, but is not limited to, cost of borrowing accounted for as interest expense.

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