Long Term Debt - Schedule of Long-term Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 30, 2017	Jul. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 224,287	$ 224,000
Fees, costs and original issue discount	(8,903)	(11,460)
Long-term debt	215,384	212,973
Less current portion of long-term debt	(303)	(294)
Long-term debt, less current portion	215,081	212,679
Term Notes Payable [Member]
Debt Instrument [Line Items]
Long-term debt	224,000
Term Notes Payable [Member] \| 2016 Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term debt	223,975	223,975
Financing Arrangement [Member]
Debt Instrument [Line Items]
Long-term debt	$ 312	$ 458	$ 590

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 unamortized debt discount (premium) and debt issuance 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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