Long-term Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Debt Instrument [Line Items]
Capital lease obligations	$ 30,222	$ 27,091
Total long-term debt	289,222	245,591
Less current maturities	3,168	3,285
Noncurrent portion of long-term debt	286,054	242,306
Revolving credit facility, due 2022 [Member]
Debt Instrument [Line Items]
Revolving loans due	259,000	0
Revolving credit facility, due 2020 [Member]
Debt Instrument [Line Items]
Revolving loans due	$ 0	$ 218,500

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

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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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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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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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