Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Millions	12 Months Ended
Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)
Number of States in which Entity Operates	8
Interest Costs Capitalized	$ 0.7	$ 0.6	$ 0.4
Deposits Assets	18.7
Advertising Expense	$ 2.7	$ 2.2
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Top Ten Customers [Member]
Concentration Risk, Percentage	52.00%	55.00%
Other Assets [Member]
Debt Issuance Costs, Net	$ 0.4
Current and Non-Current Portion of Long Term Debt [Member]
Debt Issuance Costs, Net	$ 0.9
Seneca Food Plants [Member]
Number of Real Estate Properties	26

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment in the future.

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Amount of interest capitalized during the period.

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The number of real estate properties owned as of the balance sheet date.

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The number of states the entity operates in as of the balance sheet date.

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