Note 7 - Goodwill (Details Textual) - USD ($) $ in Thousands	6 Months Ended
Jun. 27, 2020	Jun. 29, 2019
Goodwill, Impairment Loss	$ 0	$ 0

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration