Note O - Share-based Compensation - Compensation Cost Charged to Expense Under All Stock-based Incentive Awards (Details) - USD ($)	3 Months Ended	6 Months Ended
Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020
Share-based compensation expense	$ 29,000	$ 29,000	$ 58,000	$ 58,000
Share-based Payment Arrangement, Option [Member]
Share-based compensation expense	23,000	21,000	44,000	42,000
Restricted Stock [Member]
Share-based compensation expense	$ 6,000	$ 8,000	$ 14,000	$ 16,000

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=122041274&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120381028&loc=d3e5070-113901

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