Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Millions	12 Months Ended
Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)
Number of States in which Entity Operates	9
Interest Costs Capitalized	$ 0.5
Debt Issuance Costs, Current, Net	1.3
Debt Issuance Costs, Noncurrent, Net	0.4
Advertising Expense	$ 3.7	$ 3.5	$ 2.7
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Top Ten Customers [Member]
Concentration Risk, Percentage	56.00%	53.00%
Seneca Food Plants [Member]
Number of Real Estate Properties	27

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

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