Note N - Stockholders' Equity (Details Textual) - USD ($)			9 Months Ended	12 Months Ended			171 Months Ended
	Mar. 27, 2015	Mar. 10, 2015	Dec. 27, 2015	Mar. 31, 2019	Mar. 25, 2018	Mar. 26, 2017	Dec. 27, 2015	Feb. 01, 2016	Nov. 03, 2015	Sep. 11, 2015	Mar. 29, 2015	Sep. 11, 2014	Jun. 05, 2013
Special Cash Dividend [Member] | Scenario, Forecast [Member]
Payments of Ordinary Dividends, Common Stock				$ 125,000	$ 125,000	$ 375,000
Special Cash Dividend [Member]
Common Stock, Dividends, Per Share, Declared	$ 25	$ 25
Payments of Ordinary Dividends, Common Stock	$ 115,100,000		$ 375,000
Dividends Payable	$ 1,000,000
Dutch Auction Tender Offer [Member] | Minimum [Member]
Share Price									$ 41	$ 33
Dutch Auction Tender Offer [Member] | Maximum [Member]
Share Price									$ 44	$ 36
Dutch Auction Tender Offer [Member]
Treasury Stock, Shares, Acquired			88,672
Treasury Stock, Value, Acquired, Cost Method			$ 4,056,000
Stock Repurchase Program, Number of Shares Authorized to be Repurchased										500,000
Subsequent Event [Member]
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased								266,074
Stock Repurchase Program Number of Additional Shares Authorized to be Repurchased								20,000
Minimum Percentage of Common Stock Acquired by a Person or Group which Triggers Exercise of New Rights													15.00%
New Right Purchase Price													$ 100
Common Stock, Capital Shares Reserved for Future Issuance			9,191,243				9,191,243						10,188,600
Treasury Stock, Shares, Acquired			273,870				4,921,557
Treasury Stock, Value, Acquired, Cost Method			$ 11,270,000				$ 68,070,000
Share Price	$ 73.56
Common Stock, Par or Stated Value Per Share			$ 0.01				$ 0.01				$ 0.01	$ 0.01
Stock Repurchase Program, Authorized Amount												$ 6,000,000
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased			66,074				66,074