Note D - Income Per Share - Earnings Per Share Reconciliation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 23, 2018	Sep. 24, 2017	Sep. 23, 2018	Sep. 24, 2017
Net income, basic calculation	$ 4,484	$ 3,120	$ 9,279	$ 6,042
Number of shares, basic calculation (in shares)	4,188,000	4,179,000	4,187,000	4,178,000
Net income per share, basic calculation (in dollars per share)	$ 1.07	$ 0.75	$ 2.22	$ 1.45
Effect of dilutive employee stock options (in shares)	43,000	33,000	42,000	35,000
Effect of dilutive employee stock option (in dollars per share)	$ (0.01)	$ (0.01)	$ (0.03)	$ (0.02)
Net income, diluted calculation	$ 4,484	$ 3,120	$ 9,279	$ 6,042
Number of shares, diluted calculation (in shares)	4,231,000	4,212,000	4,229,000	4,213,000
Net income per share, diluted calculation (in dollars per share)	$ 1.06	$ 0.74	$ 2.19	$ 1.43