Note M - Stockholders' Equity (Details Textual) - USD ($)				6 Months Ended		12 Months Ended	30 Months Ended	180 Months Ended
	Nov. 01, 2017	Mar. 27, 2015	Mar. 10, 2015	Sep. 24, 2017	Sep. 25, 2016	Mar. 31, 2019	Sep. 24, 2017	Sep. 25, 2016	Jan. 04, 2018	Jun. 05, 2013
Common Stock, Dividends, Per Share, Declared			$ 25
Payments of Ordinary Dividends, Common Stock		$ 115,100,000		$ 125,000	$ 125,000		$ 875,000
Dividends Payable		$ 1,000,000
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				6,271,192			6,271,192			10,188,600
Treasury Stock, Shares, Acquired				0				5,127,373
Treasury Stock, Value, Acquired, Cost Method								$ 77,303,000
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased				260,258			260,258
Dividends Payable, Date of Record			Mar. 20, 2015
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared	$ 5
Dividends, Common Stock, Cash	$ 20,900,000
Dividends Payable, Date of Record	Dec. 22, 2017
Dividends Payable, Date to be Paid	Jan. 04, 2018
Scenario, Forecast [Member]
Payments of Ordinary Dividends, Common Stock						$ 125,000
Dividends Payable									$ 25,000