Note 5 - Long-term Debt - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 02, 2021	Sep. 26, 2020	Oct. 02, 2021	Sep. 26, 2020
Contractual interest	$ 568	$ 663	$ 1,753	$ 2,667
Amortization of original issuance discount and debt costs	90	92	274	300
Total interest expense related to long-term debt	$ 658	$ 755	$ 2,027	$ 2,967

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

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