Note M - Share-based Compensation - Outstanding Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands			9 Months Ended	12 Months Ended
		Mar. 29, 2015	Dec. 23, 2018	Mar. 25, 2018	[1]
Options outstanding (in shares)	[1]		68,498
Options outstanding, weighted average exercise price (in dollars per share)	[1]		$ 33.438
Options outstanding, weighted average remaining contractual life (Year)			1 year 62 days	1 year 131 days
Options outstanding, aggregate intrinsic value			$ 1,912	$ 2,648
Options granted (in shares)		50,000	10,000
Granted, weighted average exercise price (in dollars per share)		$ 53.89	$ 89.90
Granted, weighted average remaining contractual life (Year)			4 years 262 days
Options exercised (in shares)			(4,030)
Exercised, weighted average exercise price (in dollars per share)			$ 33.438
Exercised, aggregate intrinsic value			$ 224
Options outstanding (in shares)			74,468	68,498
Options outstanding, weighted average exercise price (in dollars per share)			$ 41.02	$ 33.438
Options exercisable (in shares)			64,468
Options exercisable, weighted average exercise price (in dollars per share)			$ 33.438
Options exercisable, weighted average remaining contractual life (Year)			226 days
Options exercisable, aggregate intrinsic value			$ 1,912

[1] Represents outstanding options after giving effect to the replacement options issued in connection with the Company's 2015 and 2017 special dividends.