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Note G - Employee Benefit Plans (Details Textual) - USD ($) |  | 12 Months Ended
--- | --- | ---
Jan. 01, 2004 | Jun. 30, 2018 | Jun. 30, 2017
Defined Contribution Plan, Employer Discretionary Contribution Amount |  | $ 256,000 | $ 248,000
Health Insurance Plan Premium Expense |  | $ 1,100,000 | $ 1,000,000
Number of Years Compensation Used for Benefit Obligation Assumptions |  | 5 years |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 4.10% | 3.90%
Defined Benefit Plan, Plan Assets, Contributions by Employer |  | $ 500,000 |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year |  | 0 |
Defined Benefit Plan, Expected Amortization, Next Fiscal Year, Total |  | $ 5,000 |
Large-cap Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 47.00% |
Mid-cap and Small-cap Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 27.00% |
Developed Market Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 16.00% |
Emerging Market Equity Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 9.00% |
Specialty Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 1.00% |
REIT [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 18.00% |
High-yield Fixed Income Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 17.00% |
Fixed Income Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 36.00% |
Developed Market Fixed Income Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 8.00% |
International Emerging Markets Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 21.00% |
First Contributions [Member] |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match | 100.00% |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay | 3.00% |  |
Next Contributions [Member] |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match | 50.00% |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay | 2.00% |  |

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