Note J - Income Taxes (Details Textual) - USD ($)	6 Months Ended		12 Months Ended
	Sep. 25, 2016	Sep. 27, 2015	Mar. 26, 2017	Mar. 27, 2016
Provision for Income Taxes [Member]
Excess Tax Benefit from Share-based Compensation, Operating Activities	$ 621,000
Scenario, Forecast [Member] | Minimum [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			42.00%
Scenario, Forecast [Member] | Maximum [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			44.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	36.90%	40.90%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent	6.40%
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Percent	1.20%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Investments, Percent				1.00%
Effective Income Tax Rate Reconciliation, Tax Contingency, Percent				0.20%
Effective Income Tax Rate Reconciliation, Tax Exempt Income, Percent				0.10%
Excess Tax Benefit from Share-based Compensation, Operating Activities	$ (621,000)
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	223,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	221,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	$ (31,000)