Long-Term Debt - Summary of Long-Term Debt (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total debt	$ 453,000	$ 348,000
Long-term debt	453,000	348,000
Senior Lien [Member] \| Secured Debt [Member] \| $700.0 million Credit Agreement [Member]
Debt Instrument [Line Items]
Total debt	$ 453,000
Debt instrument maturity	Mar. 27, 2023
Debt instrument, Interest Rate	Variable
Senior Lien [Member] \| Secured Debt [Member] \| Former Credit Facility [Member]
Debt Instrument [Line Items]
Total debt		$ 348,000
Debt instrument maturity		Apr. 17, 2020
Debt instrument, Interest Rate		Variable

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

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- Definition

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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