Note 3 - Business Combination (Details Textual) - USD ($)	Mar. 16, 2020	Jan. 02, 2021	Oct. 03, 2020
Restructuring Reserve, Ending Balance		$ 47,000	$ 171,000
Restructuring and Related Cost, Expected Cost Remaining		800,000,000,000
Accrued Expenses [Member]
Restructuring Reserve, Ending Balance		$ 47,000	$ 171,000
STM [Member]
Business Combination, Consideration Transferred, Total	$ 19,400,000
Business Combination, Consideration Transferred, Liabilities Incurred	$ 1,000,000.0

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Amount of expected cost remaining for the specified restructuring cost.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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