Note L - Stockholders' Equity (Details Textual) - USD ($)			9 Months Ended		12 Months Ended	183 Months Ended
	Mar. 27, 2015	Mar. 10, 2015	Dec. 25, 2016	Dec. 27, 2015	Mar. 25, 2018	Dec. 25, 2016	Sep. 09, 2016	Mar. 11, 2016	Jun. 05, 2013
Payments of Ordinary Dividends, Common Stock			$ 375,000	$ 375,000
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			6,992,892			6,992,892			10,188,600
Treasury Stock, Shares, Acquired			30,616			5,127,373
Treasury Stock, Value, Acquired, Cost Method			$ 1,272,000			$ 77,303,000
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased			260,258			260,258
MSI Agreement [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased							100,000	175,000
Special Cash Dividend [Member]
Common Stock, Dividends, Per Share, Declared	$ 25	$ 25
Payments of Ordinary Dividends, Common Stock	$ 115,100,000		$ 750,000
Dividends Payable	$ 1,000,000
Special Cash Dividend [Member] | Scenario, Forecast [Member]
Payments of Ordinary Dividends, Common Stock					$ 125,000