Note L - Share-based Compensation - Compensation Cost Charged to Expense Under All Stock-based Incentive Awards (Details) - USD ($)	3 Months Ended	6 Months Ended
Sep. 24, 2017	Sep. 25, 2016	Sep. 24, 2017	Sep. 25, 2016
Share-based compensation expense	$ 100,000	$ 173,000	$ 199,000	$ 346,000
Employee Stock Option [Member]
Share-based compensation expense	38,000	38,000	76,000	76,000
Restricted Stock [Member]
Share-based compensation expense	$ 62,000	$ 135,000	$ 123,000	$ 270,000

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration