Note 5 - Long-term Debt - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Contractual interest	$ 663	$ 1,686	$ 2,667	$ 8,991
Amortization of original issuance discount and debt costs	92	324	300	1,539
Total interest expense related to long-term debt	$ 755	$ 2,010	$ 2,967	$ 10,530

Amount of amortization expense attributable to debt issuance costs.

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

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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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