Financial instruments - Schedule Of Long-Term Debt (Details) - USD ($) $ in Thousands	Jul. 03, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
Term loan due December 2024 (2.60% at July 3, 2021)	$ 182,500	$ 190,000
Current portion of long-term debt	(15,000)	(15,000)
Unamortized debt issuance cost	(959)	(1,098)
Unamortized discount	(457)	(524)
Long-term debt, less current portion	$ 166,084	$ 173,378
Interest rate percentage	2.60%

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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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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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