Note 5 - Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jul. 03, 2021	Jul. 03, 2021	Oct. 03, 2020
Disposal Group, Including Discontinued Operation, Assets, Total	$ 6,306	$ 6,306	$ 7,778
Summerville Facility Acquired in STM Acquisition [Member]
Disposal Group, Including Discontinued Operation, Assets, Total	6,300	6,300
Summerville Facility Acquired in STM Acquisition [Member] \| Restructuring Charges [Member]
Impairment of Long-Lived Assets to be Disposed of	1,400	1,400
Non Financial [Member] \| Fair Value, Nonrecurring [Member]
Assets, Fair Value Disclosure	$ 0	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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