Note 1 - Significant Accounting Policies - Accounts Receivable (Details) - USD ($)	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Trade receivables	$ 1,300,000	$ 2,606,000	$ 1,368,000
Allowance for credit losses	(7,000)	(1,107,000)	(25,000)
Accounts receivable, net	$ 1,293,000	$ 1,499,000	$ 1,343,000