Note D - Income Per Share - Earnings Per Share Reconciliation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 24, 2017	Dec. 25, 2016	Dec. 24, 2017	Dec. 25, 2016
Net income, basic calculation	$ (3,779)	$ 699	$ 2,263	$ 6,756
Number of shares, basic calculation (in shares)	4,185,000	4,175,000	4,180,000	4,171,000
Net income per share, basic calculation (in dollars per share)	$ (0.90)	$ 0.17	$ 0.54	$ 1.62
Effect of dilutive employee stock options (in shares)		34,000	39,000	31,000
Effect of dilutive employee stock option (in dollars per share)				$ (0.01)
Net income, diluted calculation	$ (3,779)	$ 699	$ 2,263	$ 6,756
Number of shares, diluted calculation (in shares)	4,185,000	4,209,000	4,219,000	4,202,000
Net income per share, diluted calculation (in dollars per share)	$ (0.90)	$ 0.17	$ 0.54	$ 1.61