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Note M - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Dec. 23, 2018	Mar. 31, 2019	Mar. 25, 2018	Mar. 26, 2017	Feb. 27, 2017
Operating Leases, Rent Expense, Net, Total		$ 1,579	$ 1,591	$ 1,566
Operating Leases, Rent Expense, Sublease Rentals		267	274	272
Operating Leases, Rent Expense, Contingent Rentals		$ 480	478	457
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years
Guaranty Liabilities					$ 217
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
General and Administrative Expense [Member]
Operating Leases, Rent Expense, Net, Total		$ 298	287	288
Lease for Restaurant [Member]
Operating Leases, Rent Expense, Net, Total		$ 1,287	$ 1,304	$ 1,278
Minimum [Member]
Lessee, Operating Lease, Term of Contract		5 years
Lessee, Operating Lease, Renewal Term		5 years
Minimum [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Maximum [Member]
Lessee, Operating Lease, Term of Contract		20 years
Lessee, Operating Lease, Renewal Term		20 years
Maximum [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			5 years