Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ / shares in Thousands, $ in Thousands	Sep. 30, 2025	Mar. 31, 2025
Allowance for doubtful accounts receivable	$ 1,833	$ 1,186
Property, plant, and equipment accumulated depreciation	$ 28,777	$ 26,421
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, authorized (in shares)	25,000,000	25,000,000
Common stock, issued (in shares)	5,510,741	5,455,421
Common stock, outstanding (in shares)	5,510,741	5,455,421

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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