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Adoption of New Accounting Standards and Recently Issued Accounting Standards - Schedule of Adoption of Guidance Using Retrospective Method Resulted in Decreased Net Sales and Cost of Sales (Detail) - Accounting Standards Update 2014-09 [Member] - USD ($) $ in Thousands	3 Months Ended			4 Months Ended		12 Months Ended
	Dec. 30, 2017	Oct. 07, 2017	Jul. 15, 2017	Apr. 21, 2018	Apr. 22, 2017	Dec. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Decrease in net sales	$ 38,725	$ 38,246	$ 38,510	$ 42,600	$ 48,802	$ 164,283
Decrease in cost of sales	$ 38,725	$ 38,246	$ 38,510	$ 42,600	$ 48,802	$ 164,283

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- Definition

New accounting pronouncement or change in accounting principle effect of change on cost of revenue.

+ References

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- Definition

New accounting pronouncement or change in accounting principle effect of change on sales revenue net.

+ References

No definition available.

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- Definition

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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