Long-Term Debt (Schedule of Long-Term Debt) (Details) - USD ($) $ in Thousands	Jan. 02, 2021	Dec. 28, 2019	May 31, 2018
Debt Instrument [Line Items]
Total debt	$ 175,365	$ 175,229
Deferred debt issuance costs	(476)	(561)
Less: Current maturities	841	790
Long-term debt	$ 174,524	$ 174,439
Revolving credit facility with interest at a variable rate (January 2, 2021 - 1.2%; December 28, 2019 - 2.8%)
Debt Instrument [Line Items]
Fixed interest rate	1.20%	2.80%
Total debt	$ 75,000	$ 75,000
Fixed rate notes due in 2025 with an interest rate of 4.22%
Debt Instrument [Line Items]
Fixed interest rate	0.0422%		4.22%
Total debt	$ 50,000	50,000
Fixed rate notes due in 2028 with an interest rate of 4.40%
Debt Instrument [Line Items]
Fixed interest rate	0.044%		4.40%
Total debt	$ 50,000	50,000
Other amounts
Debt Instrument [Line Items]
Total debt	$ 841	$ 790

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

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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. 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 current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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