Long-Term Debt (Debt Schedule) (Details) - USD ($)	Jun. 30, 2018	Dec. 30, 2017	Mar. 10, 2015
Debt Instrument [Line Items]
Principal amount	$ 294,783,000
Line of Credit \| Term Loan
Debt Instrument [Line Items]
Principal amount	294,783,000	$ 306,791,000	$ 350,000,000
Unamortized original issue discount and debt costs	(4,558,000)	(5,616,000)	$ (3,500,000)
Less: Current portion of long-term debt	(24,526,000)	(1,508,000)
Long-term debt	$ 265,699,000	$ 299,667,000

Face (par) amount of debt instrument at time of issuance.

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

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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