Note E - Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 29, 2018	Sep. 30, 2017
Property, plant and equipment, at cost	$ 697,517	$ 653,889
Less accumulated depreciation and amortization	454,844	426,308
Property, plant and equipment, net	242,673	227,581
Land [Member]
Property, plant and equipment, at cost	2,494	2,482
Building [Member]
Property, plant and equipment, at cost	$ 26,582	26,741
Building [Member] \| Minimum [Member]
Property, plant and equipment, estimated useful life (Year)	15 years
Building [Member] \| Maximum [Member]
Property, plant and equipment, estimated useful life (Year)	39 years 182 days
Machinery and Equipment [Member]
Property, plant and equipment, at cost	$ 290,396	257,172
Machinery and Equipment [Member] \| Minimum [Member]
Property, plant and equipment, estimated useful life (Year)	5 years
Machinery and Equipment [Member] \| Maximum [Member]
Property, plant and equipment, estimated useful life (Year)	20 years
Equipment [Member]
Property, plant and equipment, at cost	$ 290,955	278,860
Equipment [Member] \| Minimum [Member]
Property, plant and equipment, estimated useful life (Year)	5 years
Equipment [Member] \| Maximum [Member]
Property, plant and equipment, estimated useful life (Year)	7 years
Transportation Equipment [Member]
Property, plant and equipment, at cost	$ 8,929	8,449
Property, plant and equipment, estimated useful life (Year)	5 years
Office Equipment [Member]
Property, plant and equipment, at cost	$ 30,752	25,302
Office Equipment [Member] \| Minimum [Member]
Property, plant and equipment, estimated useful life (Year)	3 years
Office Equipment [Member] \| Maximum [Member]
Property, plant and equipment, estimated useful life (Year)	5 years
Improvements [Member]
Property, plant and equipment, at cost	$ 38,941	38,003
Improvements [Member] \| Minimum [Member]
Property, plant and equipment, estimated useful life (Year)	5 years
Improvements [Member] \| Maximum [Member]
Property, plant and equipment, estimated useful life (Year)	20 years
Construction in Progress [Member]
Property, plant and equipment, at cost	$ 8,468	$ 16,880

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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.

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