Note 5 - Long-term Debt - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 03, 2021	Mar. 28, 2020
Contractual interest	$ 598	$ 1,086
Amortization of original issuance discount and debt costs	92	103
Total interest expense related to long-term debt	$ 690	$ 1,189

Amount of amortization expense attributable to debt issuance costs.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

+ References

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-SubTopic 10
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