Note 5 - Long-term Debt - Fair Value of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Principal amount	$ 171,875	$ 148,125
Unamortized original issuance discount and debt costs	(1,278)	(1,579)
Less: Current portion of long-term debt	(8,382)	(21,474)
Long-term debt, net of current portion and unamortized debt issue costs	$ 162,215	$ 125,072

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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