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Note G - Employee Benefit Plans (Details Textual) - USD ($) |  | 12 Months Ended
--- | --- | ---
Jan. 01, 2004 | Jun. 30, 2017 | Jun. 30, 2016
Defined Contribution Plan, Employer Discretionary Contribution Amount |  | $ 248,000 | $ 229,000
Health Insurance Plan Premium Expense |  | $ 1,000,000 | $ 847,000
Number of Years Compensation Used for Benefit Obligation Assumptions |  | 5 years |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 3.90% | 3.60%
Defined Benefit Plan, Plan Assets, Contributions by Employer |  | $ 0 |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year |  | 0 |
Defined Benefit Plan, Expected Amortization, Next Fiscal Year |  | $ 38,000 |
Large-cap Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 26.00% |
Mid-cap and Small-cap Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 46.00% |
Developed Market Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 17.00% |
Emerging Market Equity Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 10.00% |
Specialty Funds [Member] |  |  |
Defined Benefit Plan Equity Securities by Type, Percentage |  | 1.00% |
REIT [Member] |  |  |
Defined Benefit Plan Debt Securities by Type, Percentage |  | 28.00% |
High-yield Fixed Income Funds [Member] |  |  |
Defined Benefit Plan Debt Securities by Type, Percentage |  | 25.00% |
Fixed Income Funds [Member] |  |  |
Defined Benefit Plan Debt Securities by Type, Percentage |  | 24.00% |
Developed Market Fixed Income Funds [Member] |  |  |
Defined Benefit Plan Debt Securities by Type, Percentage |  | 12.00% |
International Emerging Markets Funds [Member] |  |  |
Defined Benefit Plan Debt Securities by Type, Percentage |  | 11.00% |
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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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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