Note 3 - Investments in Associated Companies (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
Mar. 28, 2021	Mar. 29, 2020	Mar. 28, 2021	Mar. 29, 2020
TNI Partners [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	50.00%		50.00%
TNI Partners [Member]
Proceeds from Equity Method Investment, Distribution	$ 1,561,000	$ 953,000	$ 2,617,000	$ 1,691,000
MNI [Member]
Proceeds from Equity Method Investment, Distribution	$ 1,150,000	$ 1,000,000	$ 1,150,000	$ 1,000,000

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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