Note 5 - Long-term Debt - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Contractual interest	$ 918	$ 2,989	$ 2,004	$ 7,305
Amortization of debt issuance costs and discount	105	528	208	1,215
Total interest expense related to long-term debt	$ 1,023	$ 3,517	$ 2,212	$ 8,520

Amount of amortization expense attributable to debt issuance costs.

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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.

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