Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($)	12 Months Ended
Oct. 01, 2016	Oct. 03, 2015	Sep. 27, 2014
Machinery and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life	3 years
Machinery and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life	15 years
Building [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life	10 years
Building [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life	30 years
Land Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life	5 years
Land Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life	15 years
Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Asset, Useful Life	5 years
PC Strand Operations [Member]
Asset Impairment Charges	$ 20,000	$ 300,000
Depreciation	10,400,000	10,900,000	$ 9,800,000
Asset Impairment Charges	20,000	543,000	0
Interest Costs Capitalized	0	$ 0	$ 0
Goodwill, Impairment Loss	$ 0

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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Amount of interest capitalized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Allowance for Funds Used during Construction
-URI http://asc.fasb.org/extlink&oid=6504829

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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