Note O - Share-based Compensation - Compensation Cost Charged to Expense Under All Stock-based Incentive Awards (Details) - USD ($)	3 Months Ended
Jun. 28, 2020	Jun. 30, 2019
Share-based compensation expense	$ 29,000	$ 28,000
Share-based Payment Arrangement, Option [Member]
Share-based compensation expense	21,000	21,000
Restricted Stock [Member]
Share-based compensation expense	$ 8,000	$ 7,000

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
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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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