Note I - Leases (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020
Operating Lease, Payments	$ 314,000		$ 881,000
Operating Lease, Weighted Average Remaining Lease Term (Year)	7 years 1 month 6 days		7 years 1 month 6 days
Operating Lease, Weighted Average Discount Rate, Percent	5.60%		5.60%
Operating Lease, Lease Income, Lease Payments	$ 463,000	$ 444,000

Amount of operating lease income from lease payments paid and payable to lessor. Excludes variable lease payments not included in measurement of lease receivable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=121640914&loc=SL77927221-108306

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Weighted average discount rate for operating lease calculated at point in time.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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