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Note H - Employee Benefit Plans (Details Textual) - USD ($)		12 Months Ended
	Jan. 01, 2025	Jun. 30, 2026	Jun. 30, 2025
Health Insurance Plan Premium Expense		$ 1,600,000	$ 1,600,000
Deferred Compensation Arrangement with Individual, Cash Award Granted, Amount		900,000	200,000
Deferred Compensation Arrangement with Individual, Cash Award Forfeited, Amount		$ 100,000	$ 0
Number of Years Compensation Used for Benefit Obligation Assumptions (Year)		5 years
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		5.42%	5.29%
Defined Benefit Plan, Plan Assets, Contributions by Employer		$ 49,000	$ 48,000
Large-cap Funds [Member]
Defined Benefit Plan Equity Securities by Type, Percentage		67.00%
Mid-cap Funds [Member]
Defined Benefit Plan Equity Securities by Type, Percentage		16.00%
Developed and Emerging Markets [Member]
Defined Benefit Plan Equity Securities by Type, Percentage		11.00%
Small Cap Funds [Member]
Defined Benefit Plan Equity Securities by Type, Percentage		6.00%
Fixed Income Funds [Member]
Defined Benefit Plan Equity Securities by Type, Percentage		54.00%
Corporate, Foreign, or Emerging Market Funds [Member]
Defined Benefit Plan Equity Securities by Type, Percentage		46.00%
Money Market Funds [Member]
Defined Benefit Plan Equity Securities by Type, Percentage		96.00%
Commodities Investment [Member]
Defined Benefit Plan Equity Securities by Type, Percentage		4.00%
First Contributions [Member]
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%
Profit-sharing Plan [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount		$ 400,000	500,000
Discretionary Profit-sharing Plan [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount		$ 0	$ 0