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Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions | Jun. 30, 2018 | Dec. 30, 2017
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Patent Related Litigation Matter |  |
Loss Contingencies [Line Items] |  |
Loss contingency accrual | $ 30.9 | $ 30.9
Employment Related Litigation Matter |  |
Loss Contingencies [Line Items] |  |
Loss contingency accrual | $ 15.0 | $ 15.0

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- Definition Amount of loss contingency liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
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