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Stock Plans - Additional Information (Detail) - Performance-based stock unit - shares | 1 Months Ended | 12 Months Ended
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May 31, 2018 | Jul. 31, 2017 | May 31, 2017 | Dec. 30, 2017 | Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Other than options, granted | 81,300 | 47,900 | 98,500 |  | 289,900
Performance period (years) |  |  |  | 3 years |
Net debt to EBITDA ratio |  |  |  |  | 450.00%
Debt ratio achievement percentage |  |  |  |  | 166.67%

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- Definition Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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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. + Details
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- Definition Debt ratio achievement percentage. + References No definition available. + Details
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- Definition Net debt to EBITDA ratio. + References No definition available. + Details
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- Details
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