Note K - Income Taxes (Details Textual) - USD ($)	3 Months Ended	12 Months Ended
Jun. 24, 2018	Jun. 25, 2017	Mar. 31, 2019
Effective Income Tax Rate Reconciliation, Percent, Total	26.40%	39.70%
Effective Income Tax Rate, Effect of Stock Compensation	1.00%	1.60%
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 63,000	$ 78,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	281,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	$ 226,000
Scenario, Forecast [Member] \| Minimum [Member]
Effective Income Tax Rate Reconciliation, Percent, Total			27.00%
Scenario, Forecast [Member] \| Maximum [Member]
Effective Income Tax Rate Reconciliation, Percent, Total			30.00%

Represents effect of stock compensation on effective income tax rate.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 15
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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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-Publisher FASB
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