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. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Share-based compensation expense	$ 29,000	$ 30,000	$ 58,000	$ 58,000
Share-based Payment Arrangement, Option [Member]
Share-based compensation expense	21,000	22,000	42,000	43,000
Restricted Stock [Member]
Share-based compensation expense	$ 8,000	$ 8,000	$ 16,000	$ 15,000

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
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-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
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-URI http://asc.fasb.org/extlink&oid=115993241&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
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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