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Adoption of New Accounting Standards and Recently Issued Accounting Standards - Additional Information (Detail) - Accounting Standards Update 2014-09 [Member] - USD ($) $ in Thousands | 3 Months Ended | 4 Months Ended | 12 Months Ended
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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 sales revenue net. + References No definition available. + Details
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